Leg : 81 Top/Bottom Interval(mm): 350/ 540 Analyst:
Hole: 553A Sample Midpoint (m) : 499.54
Core: 37 Top of Core Depth (m) : 493.00
Sect: 5 Top of Section Depth(m): 499.35
LITHOLOGY: BASALT;
Comments : PROBABLY SAME AS CORE 38,CONTACT APPEARS CHILLED
WITH PALAGONITE;
Replacement: PALAGONITE
Leg : 81 Top/Bottom Interval(mm): 0/ 200 Analyst:
Hole: 553A Sample Midpoint (m) : 499.74
Core: 37 Top of Core Depth (m) : 493.00
Sect: CC Top of Section Depth(m): 499.64
LITHOLOGY: BASALT;
Leg : 81 Top/Bottom Interval(mm): 0/ 790 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 503.29
Core: 38 Top of Core Depth (m) : 502.50
Sect: 1 Top of Section Depth(m): 502.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (0-20), 2 (22-35), 3 (33-52), 4 (53-61),
5 (61-70), 6 (70-79);
Texture : UNIFORM SIZE DISTRIBUTION OF VESICLES, PCE 3 HAS
LARGE ANGULAR "CLAST WITH DIFFUSE RIM EXHIBITING
MARKEDLY LESS VESICULARITY, APHYRIC;
Structure : IN PCE 3 BASALT FRACTURE FACES COVERED IN CALCITE,
IN PCE 2 CALCITE(?) VEIN INCLINED AT 60 DEGREES AND
VEINS DIP AT 50 AND 30 DEGREES;
Alteration : YELLOWISH GREY (578/1) TO LIGHT GREY (N7)
IRREGULAR PATCHES OF CALCITE AND QUARTZ IN PCE 1;
Comments : PCE 6 IS BASE OF UNIT, PCE 1 IS DARK GREY (N3);
Vesicles : Size(mm): 1 Percent:
Location: Filling: SMEC
ALL VESICLES FILLED WITH SMEC, IN PCE 1 VESICLES
DIP AT 45 DEGREES, UNIFORM SIZE DISTRIBUTION OF
VESICLES CA. 0.1CM OR LESS;
Groundmass : PLAGIOCLASE
PLAG LATHS;
Replacement: SMECTITE
QUARTZ
CALCITE
Leg : 81 Top/Bottom Interval(mm): 800/1460 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 503.96
Core: 38 Top of Core Depth (m) : 502.50
Sect: 1 Top of Section Depth(m): 503.30
LITHOLOGY: VESICULAR PHYRIC BASALT;
Piece No. : PCES 7 (79-113), 8 (114-126), 9 (127-135),
10 (136-146);
Texture : PHYRIC;
Structure : PCE 7 IS IRREGULARLY VEINED ROCK;
Alteration : IN PCE 7 ABUNDANT DUSKY BLUE GREEN (5BG3/2)
PATCHES;
Comments : BASE OF UNIT AND TOP OF NEXT UNIT BETWEEN PCES 6 AND
7, PCE 7 IS MEDIUM-DARK GREY (N4) AND PCE 8 IS
MEDIUM GREY (N5);
Vesicles :
Location: Filling: SMEC
HIGHLY VESICULAR BASALT, IN PCE 8 VESICLES HIGHLY
IRREGULAR BUT TOWARDS TOP OF UNIT SHOW PREFERRED
VERTICAL ORIENTATION AND OCCASIONAL VESICLES
FILLED WITH GREYISH BLUE GREEN (5BG5/2) MATERIAL,
PCES 8+9 ARE MARKEDLY LESS VESICULAR BUT VESICLES
COMMONLY INFILLED WITH GREYISH BLUE GREEN MINERAL,
SPARSE UNFILLED VESICLES;
Size(mm): 5 Percent:
IN PCE 10 ABUNDANT LARGE VESICLES INFILLED WITH
LIGHT GREY (N6-N7) MINERAL, VESICLES PART
UNFILLED;
Groundmass : PLAGIOCLASE
PYROXENE
IN PCE 9+10 PLAG LATHS AND PYX, NO APPARENT
DIFFERENCE IN GNDMASS BETWEEN PCES 9+10;
Replacement: SMECTITE
CELADONITE
ID UNCERTAIN, IN PCE 7 VEINS AND VESICLES;
Leg : 81 Top/Bottom Interval(mm): 0/1350 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 505.35
Core: 38 Top of Core Depth (m) : 502.50
Sect: 2 Top of Section Depth(m): 504.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCE 1 (2-11), 2 (12-21), 3 (21-41), 4A (42-55),
4B (55-59), 4C (59-65), 4D (65-70), 4E (70-83),
5 (84-95), 6 (94-106), 7A (107-116), 7B (116-125),
8 (125-135);
Texture : PHYRIC;
Comments : MEDIUM LIGHT GRAY (N7), GRADATIONAL BOUNDARY AT
102CM, IN PCE 8 POSSIBLE CONTACT IN OVERLYING
PEBBLE? AND SOME INDICATION OF NEAR VERTICAL
PREFERRED CIRCULATION;
Vesicles : Size(mm): 2-4 Percent:
Location: Filling: QUARTZ,CALCITE
Location: Filling: SMEC
GENERAL TREND IS A DOWNWARD DECREASE IN VESICLE
SIZE FROM 0.4-0.2CM TOWARDS 95CM, INFILLING
OF VESICLES ALSO PROGRESSIVELY INCREASES OVER
THIS INTERVAL, INFILLING OF YELLOWISH GRAY
(5Y8/1) MATERIAL - MAY BE QUARTZ+CALCITE, SMALLER
VESICLES ARE INFILLED BY SMEC AND QUARTZ;
Size(mm): >1 Percent:
IN PCES 6+7 ABUNDANT SMALL VESICLES, UNFILLED
VESICLES SPARSE;
Location: Filling: QUARTZ,CALCITE
IN PCE 8 VESICLE SIZE LARGER, LARGER VESICLES
INFILLED BY BLUISH WHITE (5B9/1) MINERAL
(QUARTZ+CALCITE);
Replacement: QUARTZ
CALCITE
SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/ 400 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 505.90
Core: 38 Top of Core Depth (m) : 502.50
Sect: 3 Top of Section Depth(m): 505.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 38-2;
Piece No. : PCE 1 (0-17);
Texture : PHYRIC;
Comments : BASE OF UNIT AT 10CM, SMALL PEBBLES OF BASALT
EXTENSIVELY COLORED LIGHT BLUE GREEN (5BG6/6),
MEDIUM GRAY (N7);
Leg : 81 Top/Bottom Interval(mm): 0/1340 Analyst:
Hole: 553A Sample Midpoint (m) : 513.34
Core: 39 Top of Core Depth (m) : 512.00
Sect: 1 Top of Section Depth(m): 512.00
LITHOLOGY: PHYRIC TO APHYRIC BASALT;
Piece No. : PCES 1 (0-12), 2 (12-22), 3 (30-37), 4 (38-50),
5 (53-58), 6 (58-70), 7 (70-77), 8A (77-84),
8B (81-97), 8C (97-105), 9 (105-112), 10 (113-122),
11 (124-132);
Texture : APHYRIC TO PHYRIC;
Alteration : EXT;
Comments : MEDIUM GRAY N4;
Vesicles :
Location: S Filling: MEC
DIFFERENT SIZED VESICLES WHICH ACCORDING TO
DIAMETER SHOW BLACK (N1) RIMS WHICH ARE VOID
AND ALSO FILLED WITH WHITE BLUISH GREEN (5BG4/6)
AND BLACK MICRO-CRYPTOCRYSTALLINE MINERAL
IDENTIFIED BY XRD AS SMEC, WITH DEPTH VESICLES
BECOME LESS AND SMALLER IN SIZE, IN PCE 1
VERTICALLY ORIENTED VESICLES WHICH ARE FILLED WITH
BLUE GREEN AND BLACK SMEC;
Replacement: SMECTITE
BLACK AND BLUE GREEN IN COLOR;
Leg : 81 Top/Bottom Interval(mm): 0/ 380 Analyst:
Hole: 553A Sample Midpoint (m) : 513.88
Core: 39 Top of Core Depth (m) : 512.00
Sect: 2 Top of Section Depth(m): 513.50
LITHOLOGY: BASALT;
Piece No. : PCE 1 (2-7), 2 (10-26), 3 (30-37);
Texture : EXT;
Comments : MEDIUM GRAY AS ABOVE;
Vesicles : Size(mm): TO 8 Percent:
IN PCE 3 FEW VESICLES UP TO 8MM;
Leg : 81 Top/Bottom Interval(mm): 0/ 290 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 521.79
Core: 40 Top of Core Depth (m) : 521.50
Sect: 1 Top of Section Depth(m): 521.50
LITHOLOGY: VESICULAR BASALT;
Leg : 81 Top/Bottom Interval(mm): 0/ 290 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 521.79
Core: 40 Top of Core Depth (m) : 521.50
Sect: 1 Top of Section Depth(m): 521.50
LITHOLOGY: CHERT;
Piece No. : PCE 1 (1-3), 2 (5-10), 3 (15-22), 4 (25-29);
Comments : GRAYISH GREEN (5/G5/2) PCE OF CHERT (QUARTZ AND LOW
CRYSTOBALITE) IN PCE 1, IN PCE 4 GRAYISH GREEN
(10G/4/2) CHERT (QUARTZ, LOW CRYSTOBALITE,
CELADONITE) LINING BLACK PATCHES;
Vesicles : VESICULAR, PCE 1 IS HIGHLY VESICULAR;
Size(mm): 0.3-0.7 Percent:
IN PCES 2+3 VESICLES WITH GREEN (5G5/12)
AMORPHOUS(?) LINING;
Leg : 81 Top/Bottom Interval(mm): 290/1370 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 522.87
Core: 40 Top of Core Depth (m) : 521.50
Sect: 1 Top of Section Depth(m): 521.79
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCE 5 (31-39), 6 (41-47), 7 (50-102), 8 (103-137);
Texture : PHYRIC;
Comments : EXTREMELY VESICULAR BASALT AT TOP OF SECTION
PROBABLY REPRESENTS TOP OF FLOW, PRESENCE OF
CELAD IN CHERT INDICATES SUBMARINE ENVIRONMENT,
UNIFORM GRAY (N5) COLOR;
Vesicles : Size(mm): 1-3 Percent:
Location: Filling: QUARTZ,CALCITE
MAJOR VARIATIONS ARE IN THE PRESENCE OF INFILLED
VESICLES ESPECIALLY IN 6+7B+7E, TOWARDS THE BASE
(8C) VESICLES BECOME MORE ABUNDANT AND ARE
PARTIALLY OPEN (SIZE 1-3MM), VESICLES IN PCES 6+
7B+7E ARE CONCENTRIC IN CIRCULAR PATCHES WITHIN
WHICH THERE IS SOME SUGGESTION OF A PREFERRED
ORIENTATION PERPENDICULAR TO THE AXIS OF THE CORE,
VESICLES ARE INFILLED WITH BLACK N.2.5 MINERAL PAR
INFILLED VESICLES ARE LINED WITH BLACK MINERAL-
FORMING AMYGDULES, OCCASIONAL WHITE MINERAL
COMPLETELY INFILLS AMYGDULES (QUARTZ+CALCITE), IN
MORE UNIFORM PHYRIC BASALT SMALLER VESICLES (1MM O
LESS) ARE PREDOMINENT;
Groundmass : FELDSPAR
LATHS OF FELDSPAR ARE APPARENT;
PYROXENE
PYX OR ALTERED PYX (10Y6/6) IN GNDMASS;
Replacement: PYRITE
OCCASIONAL SPECS OF PYRITE, IN GROUNDMASS;
QUARTZ
CALCITE
Leg : 81 Top/Bottom Interval(mm): 0/1360 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 524.36
Core: 40 Top of Core Depth (m) : 521.50
Sect: 2 Top of Section Depth(m): 523.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCE 1 (2-29), 2A (29-49), 2B (49-58), 2C (58-100),
2D (100-106), 2E (106-110), 2F (110-120),
2G (110-136);
Texture : PHYRIC;
Comments : GRAY TO DARK GRAY (N4-N5), IN PCES 2E+F ONE
PROMINENT BAND OF VESICLES SHOWS A DISTINCT
HORIZONTAL ORIENTATION ALTHOUGH SOME KIND OF
"FLOW LINE" DEFINES ITS UPPER SURFACE;
Vesicles : PRINCIPAL VESICLE VARIATIONS DOWN SECTION ARE OF
TWO TYPES-FROM TWO SIZE POPULATIONS;
Size(mm): <0.5 Percent:
FIRST GROUP LESS THAN 0.5MM SCATTERED UNIFORMILY
THROUGHOUT BASALT;
Size(mm): 1-2 Percent:
SECOND GROUP CONCENTRATED IN CIRCULAR PATCHES,
THESE PATCHES VARY IN SIZE FROM 2-3CM DOWN TO
1CM, SOME HAVE (PCE 2G FOR EXAMPLE) CLEAR
REACTION RIMS AROUND THEM, THE PATCHES OF UNFILLED
VESICLES SHOW NO PREFERRED ORIENTATION, ONE
PROMINENT BAND OF VESICLES (2E+F) SHOWS A
DISTINCT HORIZONTAL ORIENTATION, VESICLES
GENERALLY COMPOSED OF OLIVE GRAY (5Y3/2) MINERAL
WITH SPARSE TO RARE MINUTE WHITE NUCLEI;
Groundmass : PLAGIOCLASE
Size(mm): 1
LATHS OF PLAG 1MM IN LENGTH;
PYROXENE
GREEN MINERALS (PYROXENES);
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 526.00
Core: 40 Top of Core Depth (m) : 521.50
Sect: 3 Top of Section Depth(m): 524.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCE 1A (0-26), 1B (26-42), 1C (42-103),
1D (104-131), 1D (132-145), 1F (145-150);
Texture : PHYRIC;
Structure : A VEIN ADJOINING THE VESICLE AND JUST BELOW IS
FILLED WITH A LIGHT GRAY (N6) MINERAL (QUARTZ+
CALCITE), IN PCE 4F A LIGHT GRAY (N6) VEIN (5MM)
DIPS AT 45 DEGREES-PROBABLY QUARTZ PLUS CALCITE,
THE MOST REMARKABLE FEATURE OF THE SECTION IS THE
PRESENCE OF A WELL DEVELOPED SET OF HORIZONTAL
AND DIPPING FRACTURES NOW INFILLED WITH SMEC,
FRACTURES ARE MOST ABUNDANT IN 4A+4B WHERE THEY ARE
REGULARLY SPACED ABOUT 3MM, BELOW 4B THE FRACTURES
DECREASE IN ABUNDANCE BUT ARE ALSO INCLINED AT ABOUT
30 DEGREES (PCE 4C), SPARSE SUB-HORIZONTAL FRACTURES
ARE PRESENT DOWN 4D BUT INCREASE IN ABUNDANCE IN THE
LOWER PART WHERE THEY HAVE THE SAME SPACING AS
ABOVE, VEINING POST-DATES THESE FRACTURES;
Comments : DARK GRAY TO GRAY (N5-N4);
Vesicles : Size(mm): 1-30 Percent:
Location: Filling: MONT
VESICLES RANGE IN SIZE FROM 1MM TO 3CM, LARGER
VESICLES HAVE THIN (1MM) LINING AND GREEN
(MONT?) CORE, LARGER VESICLES IN SECTION 4-2
HAVE BLACK LINING AND BROWNISH GRAY INFILL
(2.5Y6/2) SMEC, IN SOME VESICLES THE BLACK
MINERAL SEEMS TO BE INGROWING AT THE EXPENSE OF
THE GREEN MONT, BELOW VEIN IN PCE 4F THERE IS AN
OBLATE PATCH OF THE VESICLES DESCRIBED FROM
SECTION 40-2;
Groundmass : PLAGIOCLASE
PLAG LATHS;
PYROXENE
GREEN, ID UNCERTAIN;
Replacement: SMECTITE
MONTMORILLONITE
ID UNCERTAIN;
QUARTZ
CALCITE
Leg : 81 Top/Bottom Interval(mm): 0/1460 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 527.46
Core: 40 Top of Core Depth (m) : 521.50
Sect: 4 Top of Section Depth(m): 526.00
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (1-5), 2A (6-23), 2B (24-38), 2C (40-64),
2D (64-66), 2E (67-68), 2F (70-74), 2G (75-91),
2H (93-98), 3 (101-105), 4 (106-109), 5 (103-130),
6 (132-139), 7 (143-146);
Texture : PHYRIC, THE CHANGE IN FRACTURE PATTERN DOWN SECTION
IS ACCOMPANIED BY A GENERAL DECREASE IN CRYSTAL
SIZE SO THAT PCES 2H+3 AND THE UPPER PART OF 4 MAY
BE APHYRIC (APHANITIC?) VESICULAR BASALT;
Structure : FRACTURING APPARENT IN SAMPLES 1+2, FRACTURING IS
HORIZONTAL IN PCES 1+2H BUT BECOMES INCLINED IN 2B
DECREASING IN ABUNDANCE FROM 2D DOWNWARD, IN PCE 4 A
NUMBER OF SMALL FRAGMENTS OF BROWN (5YR3/4) TO DARK
REDDISH BROWN (SMEC- 25YR3/4), OPEN FRACTURES(?) IN
INDIVIDUAL FRAGMENTS ARE LINED WITH A GREYISH GREEN
MINERAL (5G5/2, SMEC+CELAD);
Comments : DARK GREY TO GREY (N5-N4) BASALT, THE CHANGE IN
FRACTURE ABUNDANCE AND LATH SIZE MAY INDICATE
PROXIMITY TO THE BASE OF FLOW, FRAGMENTS IN PCE 4
ARE INTERPRETED AS THE TOP OF THE LAVA FLOW BELOW,
PCES 6+7 ARE DARK GREY (5YR4/1);
Vesicles : Size(mm): 1-4 Percent:
VESICLES RANGING IN SIZE FROM 1-4MM ARE SCATTERED
UNIFORMLY THROUGHOUT THE BASALT , AS BEFORE THE
VESICLES ARE TYPICALLY LINED WITH BLACK AND HAVE
DUSKY GREEN CENTERS (5G3/2), VESICLES DECREASE
DRAMATICALLY IN SIZE BELOW 2F, VESICLES IN PCE 2D
AND BELOW ARE COMMONLY ONLY PARTLY FILLED;
Size(mm): 3-4 Percent:
Location: Filling:
Shape : ELONGATE
PCES 6+7 ARE VESICULAR BASALT WITH LARGE
ELONGATED IRREGULAR VESICLES WHOSE LONG AXES ARE
VERTICAL, VESICLES ARE PARTLY FILLED WITH DARK
GREY (5Y4/1) MINERAL;
Phenocrysts: PYROXENE
GREEN, ID UNCERTAIN;
Groundmass : FELDSPAR
PLAGIOCLASE
Size(mm): >1
PLAG LATHS IN PCES 6+7;
PYROXENE
CRYSTALS, ID UNCERTAIN;
Replacement: SMECTITE
CELADONITE
Leg : 81 Top/Bottom Interval(mm): 0/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 532.47
Core: 41 Top of Core Depth (m) : 531.00
Sect: 1 Top of Section Depth(m): 531.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 1 (0-7), 2 (8-16), 3 (17-24), 4 (26-29),
5 (30-37), 6 (39-40), 7 (42-44), 8 (47-50),
9 (51-62), 10 (62-69), 11 (70-75), 12 (77-80),
13 (83-88), 14 (90-93), 15 (97-105), 16 (107-111),
17 (115-121), 18 (124-129), 19 (135-138),
20 (141-147);
Texture : PHYRIC;
Structure : MINOR SUB-HORIZONTAL FRACTURING APPARENT AND LINKS
VESICLES IN SEVERAL CASES, SUB-HORIZONTAL
FRACTURING APPARENT IN PCES 7-9, NEAR VERTICAL
FRACTURING IN 12+13+15 BECOMES SUB-HORIZONTAL IN
PCE 20, LARGE VEIN IN PCE 9 PROBABLY RELATED TO
FRACTURES AND MAY BE INFILLED WITH CALCITE AND
QUARTZ, FRACTURES ARE INFILLED WITH BLACK MINERAL;
Comments : DARK GREY TO GREY (N4-N5);)
Vesicles : Size(mm): 1-5 Percent:
ABUNDANT VESICLES FILLED AND PARTLY FILLED AND
RANGING IN SIZE FROM 5MM TO LESS THAN 1MM,
VESICLES TYPICALLY CONSIST OF BLACK RIM WITH WHOLE
OR PART FILLING OF MEDIUM GREY (N5) MINERAL;
Size(mm): 2-5 Percent:
BELOW PCE 6 SPARSE LARGE VESICLES AND RARE TO
ABSENT SMALL VESICLES (1MM), VESICLES TYPICALLY
INFILLED WITH BLACK RIM AND INTERIORS OF VESICLES
SHOWING WHITE MINERAL (CALCITE?) WITH BLACK
LINING;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
GREEN PYX GRAINS, ID UNCERTAIN;
Replacement: CALCITE
ID UNCERTAIN;
QUARTZ
Leg : 81 Top/Bottom Interval(mm): 0/ 750 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 533.25
Core: 41 Top of Core Depth (m) : 531.00
Sect: 2 Top of Section Depth(m): 532.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 41-1;
Piece No. : PCES 1 (1-10), 2 (11-17), 3 (19-25), 4 (29-35),
5 (38-42), 6 (42-45), 7 (48-51), 8 (53-46),
9 (58-61), 10 (64-67), 11 (68-72);
Texture : PHYRIC;
Structure : FRACTURING CLEAR TO PCE 8, PCE 1 SHOWS SINKING
CHANGE IN INCLINATION OF FRACTURES FROM 45 DEGREES
TO SUB-HORIZONTAL PROGRESSIVELY, PCES 4+5 ALSO SHOW
FRACTURES INCLINED AT 45 DEGREES, FRACTURING IN SOME
CASES CLOSELY RELATED TO LONG AXES OF VESICLES, WELL
DEVELOPED VEIN HAS LIGHT GREY RIM (N4)- QUARTZ AND
PALE YELLOW MINERAL (2.5Y7/4, XRD QUARTZ+CALCITE),
IN PCES 9-11 MINOR FRACTURING ONLY;
Comments : DARK GREY TO GREY PHYRIC, PCE 11 POSSIBLY BASAL PART
OF FLOW;
Vesicles : Size(mm): 0.3-5 Percent:
Location: Filling: CALCITE,QUARTZ
VESICLES RANGE FROM 0.3-5MM, NORMALLY LINED WITH
BLACK MINERAL AND INFILLED WITH CALCITE OR QUARTZ;
IN PCES 9-11 VESICLES FLATTENED PARALLEL TO
FRACTURES, VESICLES INCREASE IN SIZE AND IN
ABUNDANCE DOWNWARD AND ALSO BECOME MORE
FLATTENED, LARGE VESICLE (5MM) IN PCE 11 INFILLED
WITH CALCITE;
Replacement: CALCITE
QUARTZ
Leg : 81 Top/Bottom Interval(mm): 750/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 534.00
Core: 41 Top of Core Depth (m) : 531.00
Sect: 2 Top of Section Depth(m): 533.25
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 12 (75-105), 13 (108-111), 14 (115-120),
15 (121-123), 16 (126-135), 17 (137-141),
18 (143-148);
Texture : PEBBLES, GNDMASS BECOMES COARSER DOWNWARDS;
Structure : FRACTURES IN FRAGMENT COATED WITH LIGHT BLUE GREEN
(5BG6/6) MINERAL;
Comments : TOP OF NEXT LAVA UNIT & PALE RED (5R6/2) TO GREYISH
RED (5R4/2) BASALT (PCE 12), DARK GREY TO GREY
(N5-N4) VESICULAR BASALT;
Vesicles : VESICLES IN FRAGMENT COATED WITH LIGHT BLUE
GREEN (5BG6/6) MINERAL, PEBBLES BECOME MORE
VESICULAR TOWARD BASE, VESICLES SHOW SYSTEMATIC
CHANGE DOWNWARD;
Size(mm): 2-5 Percent:
Location: Filling:
Shape : ROUND
IN PCE 13;
Size(mm): 2-10 Percent:
IN PCES 14+15 FLATTENED VESICLES APPARENTLY
VERTICAL;
Size(mm): 1-5 Percent:
SMALL VESICLES, FLATTENED MINERAL IN PCE 16;
IN PCE 17 IRREGULAR VESICLES INFILLED WITH GREYISH
BLUE GREEN (5BG5/2) AND LIGHT GREY(N4) MINERALS
WITH SOME OPEN, IN PCE 18 IRREGULAR VESICLES
VESICLES INFILLED WITH GREY AND GREYISH BLUE GREEN
(50% INFILLED);
Groundmass : GROUNDMASS BECOMES COARSER DOWNWARD;
PLAGIOCLASE
PLAG LATHS;
PYROXENE
GREEN MINERAL GRAINS, ALTERED PYX(?);
Replacement: SMECTITE
ID UNCERTAIN;
QUARTZ
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/ 370 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 534.37
Core: 41 Top of Core Depth (m) : 531.00
Sect: 3 Top of Section Depth(m): 534.00
LITHOLOGY: VESICULAR PHYRIC BASALT;
CONTINUED FROM SECTION 41-2;
Piece No. : PCES 1 (1-4), 2 (7-10), 3 (12-16), 4 (20-23),
5 (27-34);
Texture : PHYRIC;
Structure : 1-2MM VEIN IN PCE 1, FILLED WITH SAME(?) MATERIAL AS
VESICLES;
Comments : DARK GREY TO GREY BASALT, PCE 3 IS DARK GREY
VESICULAR PHYRIC BASALT WITH NO GREEN INFILLING OF
VESICLES- STRONG POSSIBILITY THAT NOT IN PLACE,
CONTRAST IN LITHOLOGY WITH 42-1 SUGGESTS BASALT UNIT
WAS IN UNRECOVERED INTERVAL BETWEEN 41 AND 42;
Vesicles : Size(mm): 0.5 Percent:
Location: Filling:
Shape : IRREGULAR
IRREGULAR VESICLES INFILLED WITH GREYISH BLUE
GREEN MINERAL INSIDE BLACK LINING, NOT ALL
VESICLES INFILLED;
Groundmass : GROUNDMASS SAME AS ABOVE;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 542.00
Core: 42 Top of Core Depth (m) : 540.50
Sect: 1 Top of Section Depth(m): 540.50
LITHOLOGY: VESICULAR BASALT;
THIN SECTION THOLEIITIC BASALT;
Piece No. : PCES 1 (1-12), 2 (15-22), 3 (25-28), 4 (30-35),
5 (39-46), 6 (49-54), 7 (56-62), 8 (63-70),
9 (73-78), 10 (80-82), 11 (85-89), 12 (92-98),
13 (98-123), 14 (124-131), 15 (133-149);
Texture : PHYRIC, PCE 13 IS FINE-GRAINED;
Comments : DARK GREY TO GREY (N5-N4), PCE 3 NOT IN PLACE(?)
(CF: BASAL PART OF 41-3), PCE 4 IS DARK GREY TO GREY
BASALT, PCE 5 POSSIBLY NOT IN PLACE, PCE 6 IS GREY
(N5-N6);
Vesicles : Size(mm): >0.1 Percent:
IN PCE 1 MINOR VESICLES;
IN PCE 4 SEVERAL LARGE "CLASTS" WITH DUSKY BLUISH
GREEN VESICULAR CORES SURROUNDED BY PHYRIC BASALT
SEPARATED BY BLACK PARTLY CORRODED RIM(?) FROM
ADJACENT GNDMASS, IN PCE 5 VESICLES OPEN OR
PARTLY INFILLED WITH LIGHT GREY (N5-QUARTZ?) AND
SHOW FLOW STRUCTURE;
Size(mm): 0.1-0.2 Percent:
Location: Filling:
Shape : IRREGULAR
IN PCES 6-8 VESICLES 0.1-0.2MM-OCCASIONALLY 4MM,
75% INFILLED 25% OPEN-INFILLING BLACK LINING-
LIGHT GREY CORE, SPARSE GREEN INFILLING,
BINOCULAR EXAMINATION SHOWS GREEN ALSO IN LIGHT
GREY CORES (5BG5/2), VESICLES IRREGULAR;
Size(mm): <0.1 Percent:
Location: Filling: CLAY
IN PCE 9 VESICLES LESS THAN 0.1MM AND INFILLED
WITH BLACK CLAY(SMEC ?);
Size(mm): 0.2 Percent:
IN PCE 11 AND UPPER PART OF 12, VESICLES DISPOSED
IN HORIZONTAL ZONES SEPARATED BY ZONE IN WHICH
VESICLES SMALLER IN SIZE (0.1MM);
IN PCE 13 SHARP INCREASE IN ABUNDANCE OF VESICLES
AND APPEARANCE OF DISCRRETE OBLATE ZONES OF HIGH
INFILLED VESICLE CONCENTRATION, SOME SUGGESTION OF
FLOW ORIENTATION OF VESICLES;
Location: Filling: QUARTZ
LARGE CLAST OF VESICLES WITH CLEAR RIM, LARGE
VESICLE SHOWN IS NOT FILLED AND CONTAINS(?)
QUARTZ CRYSTALS, ALL IN PCE 15;
Groundmass : FELDSPAR
LATHS;
PYROXENE
Replacement: QUARTZ
CLAY
BLACK CLAY COULD BE SMEC(?);
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 543.50
Core: 42 Top of Core Depth (m) : 540.50
Sect: 2 Top of Section Depth(m): 542.00
LITHOLOGY: VESICULAR BASALT;
THIN SECTION THOLEIITIC BASALT;
Piece No. : PCES 1 (2-4), 2 (6-9), 3 (12-15), 4 (18-23),
5 (25-29), 6 (31-82), 7 (84-124), 8 (130-132),
9 (136-148);
Texture : PHYRIC;
Structure : PCE 6 DOMINATED BY HORIZONTAL TO SUB-HORIZONTAL
FRACTURES (>0.1CM) INFILLED BY BLACK MINERAL, BLACK
(N2.5) VEIN WITH QUARTZ(?) 0.2MM STRINGER, VEIN
POSSIBLY ASSOCIATED WITH MINOR MOVEMENT, PCE 7
DOMINATED BY FRACTURING-HERE MORE IRREGULAR BUT
LARGER, FRACTURES BOTH HORIZONTAL AND VERTICAL AND
INFILLED BY BLACK MINERAL, SOME EVIDENCE IN PCE 7 OF
MINOR MOVEMENT ALONG FRACTURES, PCE 9 SHOWS VERTICAL
SET OF FRACTURES PULLED CORE(?) BY CROSS CUTTING
HORIZONTAL SET ABOVE;
Comments : DARK GREY TO GREY, PCES 6+7 ARE GREY (N5);
Vesicles : Size(mm): TO 5 Percent:
Location: Filling: QUARTZ, CALCITE
PCES 1-3 SHOW VESICLE CLASTS WITH PART RIMS AND
LARGE OPEN (5MM) VESICLES WITH BLACK RIMS AND
QUARTZ(?), PCES 4+5 SHOW LARGER FLATTENED VESICLES
IN PART FILLED WITH QUARTZ AND CALCITE;
Size(mm): Percent: 10
Location: Filling: SMEC
IN PCE 6 THINNER VESICULAR CLASTS PRESENT,
VESICLES DECREASE DOWNWARD TO 10% AND ARE INFILLED
BY SMEC (BLACK);
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
GREEN PYX CRYSTALS;
Replacement: QUARTZ
SMECTITE
CALCITE
Leg : 81 Top/Bottom Interval(mm): 0/1210 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 544.71
Core: 42 Top of Core Depth (m) : 540.50
Sect: 3 Top of Section Depth(m): 543.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 42-2 AND INTO 43-1;
Piece No. : PCES 1 (1-3), 2 (5-7), 3 (11-14), 4 (18-25),
5 (27-31), 6 (33-40), 7 (41-43), 8 (46-65),
9 (67-75), 10 (78-80), 11 (82-92), 12 (94-102),
13 (105-106), 14 (108-121);
Texture : PHYRIC;
Structure : WELL DEVELOPED FRACTURES - ATTITUDE NOT
DETERMINABLE AS FRAGMENTS POSSIBLY ROTATED,
OCCASIONALLY "VESICLE CLASTS", IN PCE 8 VEIN(0.2CM),
SOME INCREMENT AS BASALT FRAGMENTS INCLUDED IN VEIN,
VEIN BLACK (2.5Y) WITH LIGHT GREY (N5/N6) STRINGER
(QUARTZ), FRACTURES PRESENT AS ABOVE BUT DIP AT 45
DEGREES AND CROSS AT VEIN, IN PCE 8 AT 63CM VEINS
EN-ECHELON FORM, MINOR FRACTURING ONLY BELOW PCE 12,
LARGE VESICULAR CLAST WITH CLEAR RIM IN PCE 12;
Comments : GREY (N5) BASALT, PCE 14 IS (N4) BASALT, CHANGE IN
COLOR POSSIBLY RELATED TO ABUNDANCE OF PLAG LATHS;
Vesicles : VESICLES INCREASE IN ABUNDANCE FROM PCE 9;
Size(mm): 10 Percent:
IN PCE 12 1CM VESICLES;
IN PCE 14 SPARSE LARGE VESICLES AND ABUNDANT SMALL
BLACK VESICLES;
Groundmass : PLAGIOCLASE
LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/ 70 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 550.07
Core: 43 Top of Core Depth (m) : 550.00
Sect: 1 Top of Section Depth(m): 550.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM SECTION 42-3;
Piece No. : PCE 1 (1-6);
Texture : PHYRIC;
Structure : MINOR FRACTURING;
Comments : DARK GREY TO GREY (N5-N6), POSSIBLY NEAR BASE OF
UNIT;
Leg : 81 Top/Bottom Interval(mm): 70/1200 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 551.20
Core: 43 Top of Core Depth (m) : 550.00
Sect: 1 Top of Section Depth(m): 550.07
LITHOLOGY: PLAG SPARSELY PHYRIC BASALT;
Piece No. : PCE 2 (8-12);
Texture : SPARSELY PHYRIC;
Alteration : BLUISH GREEN (5BG4/6) ALTERATION, RED COLOR DUE TO
ALTERATION OF PLAG AND PYX IN GNDMASS;
Comments : GREYISH RED (10R4/2);
Vesicles :
Location: Filling: SMEC, QUARTZ
VESICLES CONTAIN BLUE GREEN (5BG4/6) MINERAL
(SMEC) AND LIGHT GREY (QUARTZ);
Phenocrysts: PLAGIOCLASE
Groundmass : PLAGIOCLASE
PYROXENE
Replacement: SMECTITE
BLUE GREEN (5BG4/6);
QUARTZ
LIGHT GREY;
Leg : 81 Top/Bottom Interval(mm): 120/ 240 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 550.24
Core: 43 Top of Core Depth (m) : 550.00
Sect: 1 Top of Section Depth(m): 550.12
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCE 3 (15-24);
Comments : GREYISH RED (10R4/2) AND DARK GREY (N6);
Vesicles : VESICULAR, VESICLES IN PART INFILLED BLUE GREEN
(5BG4/6);
Leg : 81 Top/Bottom Interval(mm): 240/1360 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 551.36
Core: 43 Top of Core Depth (m) : 550.00
Sect: 1 Top of Section Depth(m): 550.24
LITHOLOGY: BASALTIC BRECCIA;
Piece No. : PCES 4A (24-29), 4B (31-39), 4C (40-49), 4D (50-60),
4E (59-72), 4F (71-91), 4G (90-112), 4H (112-120),
5 (120-127);
Texture : ANGULAR TO ROUNDED CLASTS OF GREY N6 TO REDDISH GREY
(10R5/1) PHYRIC VESICULAR BASALT, SPARSE GREY (N5)
AND GREYISH PURPLE (5PB2/2) CLASTS, CLAST SIZE RANGE
FROM 4CM TO 2MM, CLASTS SET IN GREEN (SMEC?) MATRIX,
CLASTS PROBABLY SEVERAL DIFFERENT LITHOLOGIC TYPES-
CLASTS ARE POLYMICT SHOWN BY CONTRASTING LITHOLOGIES
FOR EXAMPLE VESICULAR BASALTS WITH GREEN INFILLING
OF VESICLES AND ALSO PHYRIC BASALTS, DIFFERENT
DEGREE OF RED ALTERATION RIM AROUND BASALT CLASTS,
SOME CLASTS SHOW SUGGESTION OF CORROSION AND
PENETRATION BY THE MATRIX (CONTEMPORANEOUS
DEFORMATION?), IN PCE 4G REDDENING OF WHOLE ROCK
BECOMES MORE PERVASIVE (RED 10R3/6), VESICULARITY
BEGINS AT SAME LEVEL AND BECOMES MORE INTENSE
DOWNWARD AS DOES THE REDDENING, GREEN IN MATRIX
PROBABLY CELADONITE, PCE 5 IS DARK RED (2.5YR3/6)
GREENISH BLACK (5GY2/1) PEBBLE OF ABOVE;
Alteration : REDDENING OF WHOLE ROCK BECOMES MORE PERVASIVE
(RED 10R3/6), DIFFERENT DEGREE OF RED ALTERATION
RIM AROUND BASALT CLASTS, SOME CLASTS SHOW
SUGGESTION OF CORROSION AND PENETRATION BY THE
MATRIX (CONTEMPORANEOUS DEFORMATION ?);
Comments : MATRIX PENETRATION (CONTEMPORANEOUS DEFORMATION ?)
AND CORROSION IS SUGGESTED ON SOME CLASTS, GREEN IN
MATRIX IS PROBABLY CELADONITE;
Vesicles : VESICULAR AGGLOMERATE- VESICULARITY BEGINS AT
ABOUT 112CM AND MORE INTENSE DOWNWARD;
Leg : 81 Top/Bottom Interval(mm): 0/ 230 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 551.73
Core: 43 Top of Core Depth (m) : 550.00
Sect: 2 Top of Section Depth(m): 551.50
LITHOLOGY: BASALTIC BRECCIA;
CONTINUED FROM 43-1;
Piece No. : PCES 1 (2-22), 2 (10-22);
Texture : GREY (N5) TO REDDISH BROWN (10R3/6) CLASTS OF PHYRIC
BASALT-DUSKY GREEN TO GREEN BLACK MATRIX (5GY2/1);
Comments : BASE OF UNIT(?) AT 23CM BUT GAP POSSIBLE HERE!;
Leg : 81 Top/Bottom Interval(mm): 230/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 553.00
Core: 43 Top of Core Depth (m) : 550.00
Sect: 2 Top of Section Depth(m): 551.73
LITHOLOGY: VESICULAR BASALT;
THOLEIITIC BASALT (THIN SECTION);
Piece No. : PCES 3 (23-43), 4A (45-58), 4B (58-67), 4C (68-75),
4D (75-85), 4E (84-99), 5A (100-103), 5B (103-112),
5C (113-116), 6 (117-125), 7 (127-131), 8 (131-141),
9 (143-147);
Texture : PHYRIC;
IN PCE 5 LARGE VESICULAR CLASTS, RARE TO ABSENT
VESICLE CLASTS IN PCE 6, PHYRIC;
Alteration : DISTINCT REDDENING (10R4/6) RELATED TO ALTERATION
PYX AS WELL AS VESICLES(?), IN PCE 5 LARGE VESICLE
CLASTS (3.5CM) WITH REACTION RIM OF SMEC;
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): 1-2 Percent:
Location: Filling: SMEC
IN PCE 3, EXHIBIT PREFERRED VERTICAL CONCENTRATION
AND INCREASE IN ABUNDANCE DOWNWARD, VESICLES
INFILLED BY BLACK MINERAL (SMEC?);
Size(mm): 1-5 Percent:
Location: Filling: QUARTZ
IN PCE 4, NO PREFERRED ORIENTATION, IN PCE 4E
LARGE VESICLES INFILLED WITH LIGHT GREY (N7)
MINERAL (QUARTZ?);
Size(mm): 7.5 Percent:
IN PCE 5;
PCES 6-9 NORMALLY INFILLED WITH SMEC BUT RARE
QUARTZ+CALCITE(?) ALSO;
Groundmass : PLAGIOCLASE
PYROXENE
ALTERED;
Replacement: SMECTITE
QUARTZ
ID UNCERTAIN;
CALCITE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 554.50
Core: 43 Top of Core Depth (m) : 550.00
Sect: 3 Top of Section Depth(m): 553.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 43-2;
Piece No. : PCES 1 (2-8), 2 (9-13), 3 (15-28), 4 (29-42),
5 (45-58), 6 (61-81), 7 (81-95), 8 (96-130),
9 (131-149);
Texture : PHYRIC;
Structure : IN PCE 4 FRACTURES INCLINED AT 50 DEGREES, IN PCE 8
FRACTURES ABUNDANT- SPACED AT 0.5CM AND SUB-
HORIZONTAL, FRACTURES INFILLED BY SMEC, MEGASCOPIC
EXAM SHOWS PREFERRED SUB-HORIZONTAL ORIENTATION;
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): 20 Percent:
Location: Filling: QUARTZ
IN PCE 3, LARGE VESICLES WITH QUARTZ(?) CORE;
Location: Filling: QUARTZ, CALCITE
IN PCE 4, LARGE VESICLES INFILLED WITH QUARTZ
AND CALCITE WITH BLACK RIM, IN PCES 5-7
OCCASIONAL LARGE VESICLES INFILLED WITH QUARTZ(N8)
AND/OR CALCITE (5Y8/1);
Size(mm): 2 Percent:
Location: Filling: SMEC
IN PCES 8+9 SPARSE FILLED VESICLES;
Groundmass : PLAGIOCLASE
PYROXENE
PREFERRED SUB-HORIZONTAL ORIENTATION OF PLAG AND
PYX GRAINS IN GRNDMSS;
Replacement: SMECTITE
QUARTZ
CALCITE
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 556.00
Core: 43 Top of Core Depth (m) : 550.00
Sect: 4 Top of Section Depth(m): 554.50
LITHOLOGY: BASALT;
CONTINUED FROM 43-3;
Piece No. : PCES 1A (1-13), 1B (13-18), 1C (19-46), 1D (46-52),
1E (51-58), 1F (59-81), 1G (81-90), 2A (91-105),
2B (106-110), 2C (112-115), 2D (115-123),
2E (124-126), 3 (127-132), 4 (137-147);
Texture : PHYRIC, FROM PCE 3 POSSIBLE SLIGHT UPWARD DECREASE
IN GRAIN SIZE;
Structure : HORIZONTAL TO SUBHORIZONTAL FRACTURES INFILLED WITH
SMEC, BOTTOM OF PCE 3 VERTICAL FRACTURES, IN PCES
1D-1F FRACTURES AT 45 DEGREES, IN 1F SUB-HORIZONTAL
FRACTURES, AT PCE 2A FRACTURES DECREASE IN ABUNDANCE
TO RARE, IN PCE 2C BLACK (N1) VEIN WITH HORIZONTAL
FRACTURES;
Comments : MEDIUM GREY (N4), SHARP CONTACT AT 33CM;
Vesicles : SPARSE VESICLES;
Size(mm): 3 Percent:
Location: Filling: QUARTZ
PCE 1C, LARGE VESICLES FILLED WITH QUARTZ;
Size(mm): 3 Percent: RARE
IN PCE 1F;
Groundmass : PLAGIOCLASE
UNIFORM PLAG LATHS, IN 1F GREYISH BLUISH GREEN
(5BG5/2) MATRIX;
PYROXENE
Replacement: QUARTZ
SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/1210 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 557.21
Core: 43 Top of Core Depth (m) : 550.00
Sect: 5 Top of Section Depth(m): 556.00
LITHOLOGY: BASALT;
CONTINUED FROM 43-4;
Piece No. : PCES 1A (1-10), 1B (10-20), 1C (20-34), 1D (25-50),
1E (50-72), 1F (72-100), 1G (100-120);
Texture : PHYRIC;
Structure : IN PCE 1A FRACTURES INCLINED AT 20 DEGREES, IN PCE
1B FRACTURES RARE TO ABSENT AND IRREGULAR VEIN OF
QUARTZ+CALCITE INCLINED AT 70 DEGREES, IN PCE 10
SPARSE INCLINED FRACTURES AND VEIN INCLINED AT 70
DEGREES - LIGHT GREY (N7) AND YELLOWISH GREY (5Y8/1)
INFILLING, IN PCE 1E LARGE PARTLY ASSIMULATED CLAST,
IN PCES 1F+1G FRACTURES GENERALLY SUB-HORIZONTAL BUT
SOME SHOW CHANGE IN DIP FROM HORIZONTAL TO ABOUT 20
DEGREES;
Alteration : IN PCE 1C BLACK HALO AROUND CORE, REACTION RIM(?);
Comments : MEDIUM GREY (N5), VERTICAL CONTACT IN PCE 1C;
Vesicles :
Location: Filling: CALCITE
IN PCE 1B LARGE VEXICLE INFILLED WITH CALCITE
NEXT TO IRREGULAR VEIN, VESICLES ARE LIGHT GREY
(N7), IN PCES 1F+1G SPARSE VESICLES;
Groundmass : PLAGIOCLASE
LATHS SHOW PREFERRED ORIENTATION APPROXIMATELY
PARALLEL TO FRACTURES;
PYROXENE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1330 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 560.83
Core: 44 Top of Core Depth (m) : 559.50
Sect: 1 Top of Section Depth(m): 559.50
LITHOLOGY: BASALT;
Piece No. : PCES 1 (2-9), 2A (10-70), 2B (70-82), 2C (82-92),
2D (92-112), 2E (112-118), 2F (119-133);
Texture : PHYRIC, VERY FINE-GRAINED APHYRIC GNDMASS (BINOCULAR
EXAMINATION), DISCRETE OLIVE GREY BLEBS (0.5MM);
Structure : WHOLE SECTION CUT BY SUBHORIZONTAL FRACTURES
TYPICALLY SPACED AT 0.3 TO 0.5CM, FRACTURES INFILLED
BY BLACK CLAY MINERAL (SMEC?), NO INDICATION OF
DISPLACEMENT OF FRACTURE PATTERN BY VEINS, PROMINENT
VEINS IN PCE 2A DIP 40 DEGREES AND PCES 2E-F DIP 7O
DEGREES, INFILLING IS GREYISH BLACK (N1) WITH NEAR
COMPLETE MASSIVE INFILLING OF LIGHT OLIVE GREY (5Y5/
QUARTZ+CALCITE ?), NO INDICATION OF DISPLACEMENT OF
FRACTURE PATTERN BY VEINS;
Vesicles : Size(mm): 1-10 Percent:
Location: Filling: CALCITE,QUARTZ
SPARSE VESICLES OCCUR THROUGHOUT, INFILLED WITH
1) YELLOWISH GREY (5Y8/1, QUARTZ+CALCITE?) AND
2) DUSKY BLUE GREEN (5BG3/2);
Groundmass : PLAGIOCLASE
PLAG & A GREEN MINERAL IN GROUNDMASS;
Replacement: QUARTZ
CALCITE
ID UNCERTAIN;
SMECTITE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1420 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 562.42
Core: 44 Top of Core Depth (m) : 559.50
Sect: 2 Top of Section Depth(m): 561.00
LITHOLOGY: VESICULAR BASALT;
THOLEIITIC BASALT, CONTINUED FROM 44-3;
Piece No. : PCES 1A (0-35), 1B (35-83), 2A (84-101),
2B (100-103), 3 (105-112), 4 (116-119),
5 (121-124), 6A (127-134), 6B (135-141);
Texture : PHYRIC;
Structure : ENTIRE SECTION SHOWS WELL DEVELOPED SUB-HORIZONTAL
FRACTURES, THESE INCREASE IN ABUNDANCE AND SPACING
DOWN SECTION (SPACING O.5-1CM AT TOP TO 0.3CM AT
BASE), VEIN AT TOP DIPS 87 DEGREES AND IS WALLED
BLACK (N7) WITH VEIN INFILL OF LIGHT OLIVE GREY,
VEINS AT BASE INCLINED AT 10 DEGREES, VEINS LINED
WITH BLACK (N2) BUT LIGHT GREY (N7) TO YELLOWISH
GREY INFILLING (QUARTZ+CALCITE?);
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): 2-5 Percent:
SPARSE VESICLES OCCUR THROUGHOUT AND ARE INFILLED
WITH 1) GREYISH GREEN (10G4/2) TO GREENISH BLACK
(5GY2/1) 2) LIGHT GREY (N7), BLACK LININGS
COMMON TO BOTH;
Groundmass : PLAGIOCLASE
PYROXENE
PREDOMINANTLY FINE PLAG LATHS WITH SPARSE GREEN
PATCHES (PYX?);
Replacement: CALCITE
ID UNCERTAIN;
QUARTZ
Leg : 81 Top/Bottom Interval(mm): 0/ 700 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 563.20
Core: 44 Top of Core Depth (m) : 559.50
Sect: 3 Top of Section Depth(m): 562.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 44-2;
Piece No. : PCES 1A (3-15), 1B (15-21), 1C (22-70);
Texture : PHYRIC, MARKED CONTRAST IN GNDMASS SIZE;
Structure : FRACTURING CONTINUES DOWN TO THE TOP 5CM OF PCE 1C
BUT THEN BECOMES MINOR, IRREGULAR VEIN THAT CLOSES
UP DOWNWARD AND CONFINED TO ZONE OF COARSER GNDMASS;
Comments : MEDIUM GREY (N5), IRREGULARITIES ON OPPOSITE SIDES
OF THE VEIN IN PCE 1C MATCH- POSSIBLE COOLING CRACK;
Vesicles : Size(mm): 1-3 Percent:
VESICLES MORE ABUNDANT THAN IN LOWEST PART OF
SECTION 44-2, VESICLES INFILLED WITH DUSKY GREEN
(5G3/2) COMMONLY OR SPARSE YELLOWISH GREY (5G8/1),
VESICLES GRADE OUT AT TOP OF PCE 1C;
Leg : 81 Top/Bottom Interval(mm): 710/ 870 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 563.37
Core: 44 Top of Core Depth (m) : 559.50
Sect: 3 Top of Section Depth(m): 563.21
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 2 (71-78), 3 (81-87);
Texture : PHYRIC;
Comments : MAIN DIFFERENCE FROM OVERLYING BASALT IS COLOR AND
APPEARANCE OF OPEN VESICLES (ABSENT ABOVE), MEDIUM
DARK GREY (N4), CAUSE OF DIFFERENCE IN COLOR COULD
BE DUE TO MUCH GREATER ABUNDANCE OF GREEN MINERAL
AND SUBORDINATION OF PLAG LATHS;
Vesicles : VESICLES LINED WITH BLACK AND INFILLED WITH OR
INTERNALLY LINED WITH LIGHT GREY;
Leg : 81 Top/Bottom Interval(mm): 0/ 200 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 562.20
Core: 45 Top of Core Depth (m) : 562.00
Sect: 1 Top of Section Depth(m): 562.00
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (1-11), 2 (12-20);
Texture : PHYRIC, VERY FINE-GRAINED;
Alteration : IRREGULAR SMEC PATCHES AND OTHER GREEN MINERALS,
OCCASIONAL PYRITE;
Comments : BLACK ASH RED (5R2/2), RED GNDMASS, REDDENING DOES
NOT AFFECT VESICLES;
Vesicles : Size(mm): 1-3 Percent:
3MM AT TOP AND DECREASES DOWNWARD;
Replacement: SMECTITE
PYRITE
OCCASIONAL PYRITE;
Leg : 81 Top/Bottom Interval(mm): 220/1100 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 563.10
Core: 45 Top of Core Depth (m) : 562.00
Sect: 1 Top of Section Depth(m): 562.22
LITHOLOGY: TUFF;
Piece No. : PCES 3 (22-81), 4 (81-92), 5 (95-101), 6 (103-110);
Comments : CONTACT BETWEEN VESICULAR BASALT AND UNDERLYING TUFF
AT 25CM, UPPERMOST PART OF TUFF DARK REDDISH BROWN
(10R3/4) CONTAINS POLYMICT FRAGMENTS 1-3MM OF PHYRIC
VESICULAR BASALT, AT 27CM FAINT IRREGULAR CONTACT
SEPARATES INTERVAL (22-27) FROM MAIN PART OF TUFF,
INTERVAL (27-32) IS GREYISH RED TO DARK REDDISH
BROWN (5R4/2 TO 10R3/4) TUFF, SMALL (>0.1CM) LATHS
OF WHITE PLAG SHOWING SUBPARALLEL ORIENTATION TO
REDDENING AND IRREGULAR GREEN FLAKES OF SMEC ALSO
ELONGATED IN SAME SENSE AND LITHIC FRAGMENTS SPARSE,
INTERVAL (36-38CM) UPTURNED GREYISH RED (5R3/2)
LAMINAE WITH THICKER DUSKY RED INTERBED AND POSSIBLE
LARGE RED CLAST AND GAS ESCAPE STRUCTURE- VERTICAL
ORIENTATION OF GREEN MINERAL ON OPPOSITE SIDE OF
CORE, IN INTERVAL (38-42) GRADED BED WITH DARK
REDDISH BROWN (10R3/4) IN UPPER PART BECOMING DARK
REDDISH GREY BELOW (10R4/1), DISTINCT ZONE OF 2MM
LITHIC FRAGMENTS AT BASE, BELOW 45CM GREYISH RED
(10R4/2) TO MINOR CONVOLUTED BASE NEAR 50CM,
DISTINCT SUBHORIZONTAL ORIENTATION OF BLACK/DARK
GREEN MINERALS, DISTINCT SUBHORIZONTAL CIRCULATION
OF BLACK/DARK MINERALS, LARGE ALTERED GREYISH GREEN
(5BG5/2) WITH LIGHT BLUE GREEN FLECKS (5BG6/6),
INTERVAL (53-57) COARSER ZONE WITH 2-3MM ALTERED
CLAST ZONE IN DARK REDDISH GREY (10R3/1), INTERVAL
(57-77) DISTINCTLY LAMINATED (MM SCALE)- INTERBEDS
ARE DARK REDDISH GREY (10R3/1) AND DARK REDDISH
BROWN (10R3/4) LAMINAE EMPHASIZED BY BLACK MINERAL,
GRADING ALSO PRESENT IN THICKER BEDS, ANGULAR
CONTACTS EVIDENT ESPECIALLY AT 77.5CM, BELOW 77.5CM
REDDENING DECREASES MARKEDLY TO BLACKISH RED
(5R2/2), SEDIMENTARY CONTACT AT 75CM BETWEEN FINER-
GRAINED TUFF COARSER GRAINED BELOW, BASAL PART OF
UNIT IS VERY GREY (N3) WITH SPARSE RED PATCHES
(2.5YR/2), SMALL FELDSPAR(?) PHENOS AND GREYISH BLUE
GREEN CLAY MINERAL (5BG2/2), OCCASIONAL LARGE LITHIC
FRAGMENTS;
Leg : 81 Top/Bottom Interval(mm): 1100/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 563.50
Core: 45 Top of Core Depth (m) : 562.00
Sect: 1 Top of Section Depth(m): 563.10
LITHOLOGY: VESICULAR BASALT;
THOLEIITIC BASALT (THIN SECTION);
Piece No. : PCES 7 (110-121), 8 (122-130), 9 (131-138),
10 (141-148);
Texture : PHYRIC, AT TOP OF PCE 7 CHILLED EDGE;
Alteration : GNDMASS APPEARS DEEPLY ALTERED AND IS REDDENED;
Comments : AT TOP OF PCE 7 CONTACT WITH OVERLYING LITHIC TUFF-
CONTACT HAS LIGHT BLUE GREEN (5BG), COLOR IS
VARIEGATED FROM WEAK RED (2.5YR4/2) TO DARK GREENISH
GREY (5GY4/1) IN IRREGULAR PATCHES AND INFILLED
VESICLES, "NORMAL" COLOR OCCASIONALLY SEEN IS DARK
GREY (N2);
Vesicles : VESICULAR, WITH VESICLES BECOMING LARGER AND MORE
OPEN TOWARD BASE;
Leg : 81 Top/Bottom Interval(mm): 0/ 180 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 563.68
Core: 45 Top of Core Depth (m) : 562.00
Sect: 2 Top of Section Depth(m): 563.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (1-9), 2 (11-18);
Texture : PHYRIC, AT 5CM LARGE LITHIC CLAST SURROUNDED BY
"CHILLED"(?) MARGIN;
Comments : DARK OLIVE GREY (5YR3/2), 20CM COULD BE POSSIBLE
BASE OF FLOW(?);
Alteration : GRNDMASS RED AND PROBABLY ALTERED;
Leg : 81 Top/Bottom Interval(mm): 210/1140 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 564.64
Core: 45 Top of Core Depth (m) : 562.00
Sect: 2 Top of Section Depth(m): 563.71
LITHOLOGY: AGGLOMERATE;
Piece No. : PCES 3 (21-28), 4 (30-36), 5 (38-48), 6 (51-55),
7 (56-59), 8 (62-64), 9 (67-73), 10 (75-70),
11 (84-88), 12A (90-108), 12B (108-114);
Texture : LARGE CLASTS ARE GREY (N4) AND TYPICALLY ANGULAR
(SIZE UP TO 5CM), CLASTS SEEM TO BE POLYMICT AND
SHOW EVIDENCE OF FRACTURING AND PENETRATION BY THE
MATRIX ;
Comments : GREYISH RED PURPLE (5RP4/2) TO MEDIUM GREY (N4)
AGGLOMERATE, CLASTS SHOW EVIDENCE OF FRACTURING AND
PENETRATION BY THE MATRIX, MATRIX CONSISTS OF
SMALLER (MM) SIZE PARTICLES, REDDENING DECREASES
DOWNWARD, VESICLES OCCUR THROUGHOUT THE UNIT AND
OCCUR IN BOTH THE CLASTS AS WELL AS IN THE MATRIX,
VESICLES LINED WITH GREYISH BLUE GREEN MINERAL
(5BG5/2) AND LIGHT GREY (N7) MINERAL, BOTH ALSO SEEM
TO OCCUR IN MATRIX;
Vesicles : VESICLES OCCUR THROUGHOUT THE UNIT AND OCCUR IN
BOTH CLASTS AS WELL AS IN THE MATRIX, VESICLES
LINED WITH GREYISH BLUE GREEN MINERAL (5BG5/2) AND
LIGHT GREY (N7) MINERAL;
Leg : 81 Top/Bottom Interval(mm): 1140/1440 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 564.94
Core: 45 Top of Core Depth (m) : 562.00
Sect: 2 Top of Section Depth(m): 564.64
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 12C (114-121), 13 (127-131), 14 (133-138);
Texture : PHYRIC, UPPER SURFACE OF BASALT IS CHILLED;
Structure : COOLING CRACKS OCCUR IN PCES 13+14;
Comments : CONTACT WITH BASALT AT 115CM SHOWS PROGRESSIVE
FRACTURE OF SURFACE FLOW AND PEELING OFF OF CLASTS
OF ALL SIZES AND INCORPORATION INTO MATRIX OF
AGGLOMERATE ABOVE, CLASTS ARE MEDIUM GREY (N4) WITH
DARK GREENISH GREY (5GY4/1) INTERSTICES, BASALT IS
MEDIUM GREY (N5);
Vesicles : VESICLES ARE VERTICAL AND PROBABLY DUE TO GAS
STREAMING;
Leg : 81 Top/Bottom Interval(mm): 0/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 566.47
Core: 45 Top of Core Depth (m) : 562.00
Sect: 3 Top of Section Depth(m): 565.00
LITHOLOGY: VESICULAR BASALT;
THOLEIITIC BASALT (THIN SECTION), CONTINUED FROM
SECTION 45-2;
Piece No. : PCES 1 (1-7), 2 (8-11), 3 (12-25), 4 (27-29),
5A (30-40), 5B (41-46), 5C (47-52), 5D (52-61),
6 (62-90), 7 (91-102), 8 (104-108), 9 (110-117),
10 (119-121), 11 (122-130), 12 (131-137),
13 (139-147);
Texture : PHYRIC, HOST BASALT CHILLED AGAINST CLAST IN PCE 6,
GNDMASS GRAIN SIZE DECREASES DOWNWARD TO CHILLED
CONTACT AT BASE OF UNIT, IN PCE 6 LARGE CLAST OF
MEDIUM DARK GREY (N4) VESICULAR BASALT;
Structure : IN PCE 6 SUBHORIZONTAL FRACTURES SPACED AT 3MM,
VESICLES FLOW BANDED IN PCE 6, IN PCE 13 SPARSE
INCLINED FRACTURES, VERTICAL FRACTURES NEAR BASE OF
PEBBLE INFILLED WITH DUSKY GREEN (5G3/2) MINERAL,
PCE 6 LARGE CLAST OF MEDIUM DARK GREY (N4) VESICULAR
BASALT, EXOTIC;
Alteration : GNDMASS POSSIBLY DEEPLY ALTERED;
Comments : BASALT IS MEDIUM GREY (N5-N6), IN PCE 13 SMALL
PEBBLE OF AGGLOMERATE FROM TOP OF UNDERLYING UNIT IS
AT EDGE OF PEBBLE;
Vesicles : INTERVAL (0-39) VESICLES (MM SCALE) ORIENTED
VERTICALLY, INTERVAL (40-92) VESICLES RANDOMLY
ORIENTED, INTERVAL (92-110) VESICLES INCLINED AT
70 DEGREES, SPARSE VESICLES IN PCE 9, VERTICAL
VESICLES IN PCE 11;
Groundmass : PLAGIOCLASE
PREDOMINANTLY FINE LATHS OF PLAG WITH GREEN
MINERAL;
Leg : 81 Top/Bottom Interval(mm): 0/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 567.97
Core: 45 Top of Core Depth (m) : 562.00
Sect: 4 Top of Section Depth(m): 566.50
LITHOLOGY: BASALTIC BRECCIA;
Piece No. : PCES 1 (1-4), 2 (8-12), 3A (15-21), 3B (21-30),
4 (31-39), 5A (40-49), 5B (49-56), 6 (57-80),
7 (81-83), 8A (87-95), 8B (95-102), 8C (102-110),
8D (111-122), 8E (122-130), 8F (130-137),
8G (138-147);
Texture : FINE-GRAINED GROUNDMASS, VESICULAR BASALT CLASTS
(GREYISH RED PURPLE (5RP4/2) TO PALE RED PURPLE
(5RP6/2)), REDDENING DECREASES DOWNWARD SO CLAST
ABOVE FLOW ARE PREDOMINANTLY GREYISH RED PURPLE
(5RP4/2) TO MEDIUM GREY (N5);
Structure : FRACTURES INCLINED AT 45 DEGREES IN PCE 8F;
Comments : AT 22CM CONTACT AGGLOMERATE/BASALT IRREGULAR NEAR
VERTICAL, FRAGMENTS CLEARLY BEING BROKEN OFF BASALT
AND INCORPORATED IN AGGLOMERATE CHILLING OF FLOW
SURFACE, ALSO EVIDENCE OF FLOW BANDING AND FOLDING
OF VESICLES, INCLINED VESICLES AND WISPS OF MEDIUM
GREY (N5) INDICATE FLOW FOLDING, ALSO PRESENT WITHIN
LIMBS OF FOLD ARE SEVERAL LARGE VESICULAR CLASTS
SHOWING PARTIAL INCORPORATION INTO THE FLOW, MATRIX
IS DARK REDDISH BROWN (2.5YR/8);
Vesicles : IN PCE 5A VERTICAL VESICLES (GAS STREAMING), IN
PCE 5B GAP IN VESICLES, IN PCE 6 STEEPLY INCLINED
VESICLES-PREFERRED CONCENTRATION (80 DEGREE DIP),
IN PCE 8 INCLINED VESICLES, IN PCE 8E VERTICAL
VESICLES ABUNDANT, IN PCE 1F SPARSE VESICLES;
Size(mm): 3 Percent:
IN PCE 8G ABUNDANT 3MM IRREGULAR VESICLES
BECOMING SUB-HORIZONTAL IN BASE OF LAST PEBBLE;
Size(mm): 10 Percent:
SPARSE LARGE VESICLES- LIGHT GREY TO YELLOWISH
GREY (5Y8/1), VESICLES GENERALLY BLACK (N2) TO
GREENISH BLACK (5GY2/1) IN PCE 6;
Groundmass : PLAGIOCLASE
LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/1420 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 569.42
Core: 45 Top of Core Depth (m) : 562.00
Sect: 5 Top of Section Depth(m): 568.00
LITHOLOGY: BASALTIC BRECCIA;
CONTINUED FROM SECTION 45-4;
Piece No. : PCES 1A (2-4), 1B (5-17), 1C (17-25), 1D (26-35),
1E (36-46), 1F (47-55), 1G (57-65), 2 (67-80),
3 (84-87), 4A (90-102), 4B (102-128), 4C (129-141);
Texture : BASALTIC BRECCIA, PHYRIC BASALT;
Structure : INTERVAL (20-55) FRACTURING INCLINED AT 30 DEGREES,
INTERVAL (55-85) TWO LARGE VEINS LINED WITH SMEC AND
LOWER VEIN INFILLED WITH PALE PURPLE (5PG/2)- LIGHT
GREY (N7) MINERAL- UPPER YELLOWISH GREY (5Y8/1)-
SECOND GENERATION OF MINERAL GROWTH APPARENT, IN PCE
4 VERTICAL FRACTURES AND SUBHORIZONTAL TO 10 DEGREE
FRACTURES BELOW;
Comments : MEDIUM GREY BASALT IN PCE 1G;
Vesicles : INTERVAL (0-7) SUB-HORIZONTAL VESICLES, INTERVAL
(7-20) NEAR VERTICAL VESICLES;
Location: Filling: QUARTZ, CALCITE
INTERVAL (20-55) SPARSE VESICLES ORIENTED PARALLEL
TO FRACTURING INCLINED AT 30 DEGREES, THESE HAVE
LIGHT GREY (N7)- YELLOWISH GREY (5Y8/1) INFILL;
Size(mm): 2-4 Percent:
IN PCE 2 IRREGULAR LARGE VESICLES;
Size(mm): 5 Percent:
IN PCE 4A ABUNDANT VESICLES (MM SCALE WITH SPARSE
0.5CM VESICLES), VESICLES BLACK (N7) TO DARK GREEN
(5G3/2);
IN PCE 4B IRREGULAR LARGE VESICLES, SPARSE
VESICLES OCCASIONALLY CONCENTRATED IN PATCHES;
Groundmass : PLAGIOCLASE
FINE PLAG LATHS, GREEN MINERAL PRESENT;
Replacement: PYRITE
GRAINS, ID UNCERTAIN;
QUARTZ
CALCITE
SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/ 880 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 570.38
Core: 45 Top of Core Depth (m) : 562.00
Sect: 6 Top of Section Depth(m): 569.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM SECTION 45-5;
Piece No. : PCES 1A (1-10), 1B (10-21), 2A (21-36), 2B (36-52),
2C (52-61), 2D (61-72), 2E (73-86);
Texture : PHYRIC BASALT;
Structure : AT 3-5CM INCLINED VEIN AND BLACK LINING INFILLED
WITH LIGHT GREY (N7), PCE 1B INCLINED TO SUB-
HORIZONTAL FRACTURES, IN PCE 2A SUB-HORIZONTAL
INCLINED FRACTURE, IN PCE 2B VEIN IS LIGHT GREY (N7)
TO YELLOWISH GREY (5Y8/1) MINERAL (QUARTZ+CALCITE?),
SOME SUGGESTION OF GROWTH OF SMEC LINING AT EXPENSE
OF MINERAL, IN PCE 2E COMPLEX PATTERN OF SUB-
HORIZONTAL AND NEAR VERTICAL FRACTURES;
Comments : MEDIUM LIGHT GREY (N5);
Vesicles : IN PCE 2C LARGE ELONGATE INCLINED VESICLES;
Groundmass : PLAGIOCLASE
FINE PLAG LATHS, SPARSE LARGER CLASTS;
PYROXENE
GREEN MINERAL TOO SMALL TO BE RESOLVED WITH
BINOCULAR (ALTERED PYX?);
Replacement: CALCITE
ID UNCERTAIN;
QUARTZ
ID UNCERTAIN;
SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 573.00
Core: 46 Top of Core Depth (m) : 571.50
Sect: 1 Top of Section Depth(m): 571.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM SECTION 45-6;
Piece No. : PCES 1 (1-10), 2 (10-35), 3 (35-46), 4 (45-57),
5 (57-88), 6 (89-101), 7 (101-106), 8 (106-125),
9 (103-135), 10 (131-139), 11 (139-143),
12 (140-149);
Texture : PHYRIC, GNDMASS UNIFORM AND FINE-GRAINED;
Structure : INCLINED FRACTURES IN PCE 1, PRINCIPAL FEATURE OF
THE SECTION IS THE ABUNDANT FRACTURING, BLACK VEIN-
POSSIBLE COOLING CRACK;
Comments : MEDIUM LIGHT GREY (N6), SEVERAL CLASTS EXHIBITING
ABUNDANT INFILLED VESICLES OCCUR SPORADICALLY AND
SHOW VARYING DEGREES OF INCORPORATION INTO THE
BASALT;
Vesicles : VESICULAR, SEVERAL CLASTS EXHIBIT ABUNDANT
INFILLED VESICLES;
Groundmass : PLAGIOCLASE
PYROXENE
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 574.50
Core: 46 Top of Core Depth (m) : 571.50
Sect: 2 Top of Section Depth(m): 573.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM SECTION 46-1;
Piece No. : PCES 1 (0-12), 2 (12-15), 3 (14-25), 4 (24-40),
5 (40-64), 6 (64-89), 7 (90-97), 8 (98-108),
9 (110-130), 10 (130-140), 11 (140-150);
Texture : PHYRIC;
Structure : IN PCE 1 FRACTURES INCLINED 90 DEGREES- INCLINED 20
DEGREES IN PCE 3, IN PCE 4 HORIZONTAL TO SUB-
HORIZONTAL AND SPACED 2CM, IN PCE 5 SUB-HORIZONTAL
TO HORIZONTAL AND SPACED 0.5CM, IN PCE 6 FRACTURES
EXHIBIT CROSS-CUTTING (IMBRICATION?), IN PCE 9 25
DEGREE INCLINATION, IN PCE 10 SUB-HORIZONTAL,
PRINCIPAL VARIATION IN SEDIMENT IS ATTITUDE OF
FRACTURES, FRACTURE FILLING-ALTERED PYX(?);
Comments : MEDIUM GREY;
Vesicles : VESICULAR, IN PCE 8 LARGE VESICLES INFILLED WITH
GREY (N5) CORE SURROUNDED BY GREENISH BLACK
(5GY2/1);
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
ALTERED PYX FILLING FRACTURE(?);
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 576.00
Core: 46 Top of Core Depth (m) : 571.50
Sect: 3 Top of Section Depth(m): 574.50
LITHOLOGY: PHYRIC TO APHYRIC BASALT;
THIN SECTION IS THOLEIITIC BASALT, CONTINUED FROM
46-2;
Piece No. : PCES 1 (0-20), 2 (20-28), 3 (29-36), 4 (37-40),
5 (40-46), 6 (46-61), 7 (62-75), 8 (74-89),
9 (75-80), 10 (80-87), 11 (87-93), 12 (93-95),
13 (96-108);
Texture : PHYRIC TO APHYRIC;
Structure : PRINCIPAL VARIATION IN THIS SECTION IS IN BRAIDED
ASPECT OF THE FRACTURES, IN PCES 1+2 FRACTURES SUB-
HORIZONTAL WITH BRAIDED ASPECT SPACING 1-3CM, ALSO
SUB-HORIZONTAL TO HORIZONTAL BRAIDING MINOR WITH
SPACING >0.5CM IN INTERVAL (45-90), INTERVAL
(90-108) BRAIDED SUB-HORIZONTAL TO HORIZONTAL
FRACTURES, BELOW 108CM SUB-HORIZONTAL TO HORIZONTAL
FRACTURES SPACING (0.5CM) OR LESS;
Comments : MEDIUM GREY IN COLOR, BRAIDING SEEMS TO REFLECT
STREAKING OUT OF BLACK MINERAL;
Vesicles : VESICLES ARE SPARSE AND WHEN PRESENT ARE FILLED
AND 1) ALWAYS LINED WITH BLACK AND 2) CORE MAY
BE DUSKY GREEN (5G3/2) OR A COMBINATION OF LIGHT
GREY (N7) AND YELLOWISH GREY (5Y8/1);
Leg : 81 Top/Bottom Interval(mm): 0/1080 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 577.08
Core: 46 Top of Core Depth (m) : 571.50
Sect: 4 Top of Section Depth(m): 576.00
LITHOLOGY: PHYRIC TO APHYRIC BASALT;
THIN SECTION IS THOLEIITIC BASALT, CONTINUED FROM
46-3;
Piece No. : PCES 1 (0-16), 2 (17-30), 3 (31-37), 4 (37-50),
5 (50-60), 6 (60-65), 7 (65-71), 8 (71-75),
9 (75-80), 10 (80-87), 11 (87-93), 12 (93-95),
13 (96-108);
Texture : PHYRIC TO APHYRIC, SUGGESTION OF PROGRESSIVE
DECREASE IN GRAIN SIZE TOWARDS TOP OF VESICLE ZONE;
Structure : HORIZONTAL FRACTURES BRAIDING WITH SOME DECREASE IN
ABUNDANCE DOWNWARD, FRACTURES MINOR BELOW 50CM;
Comments : MEDIUM GREY (N6/N5) BASALT, BASE OF UNIT AT 104CM;
Vesicles : IN PCE 5 LARGE VESICLES INFILLED WITH LIGHT GREY
(N6) AND OLIVE GREY (5Y4/1) FLECKS AT EDGE OF
BLACK LINING;
Location: Filling:
Shape : ROUNDED
BELOW PCE 5 PROGRESSIVE INCREASE IN VESICLES
(ROUNDED), INDIVIDUAL VESICLES HAVE LONG AXES
ORIENTED VERTICALLY, OBLATE VESICLES PART OPEN AND
WHERE FILLED ARE GREYISH BLACK (N6) TO OLIVE GREY
(5Y4/1);
Leg : 81 Top/Bottom Interval(mm): 1080/1300 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 577.30
Core: 46 Top of Core Depth (m) : 571.50
Sect: 4 Top of Section Depth(m): 577.08
LITHOLOGY: VESICULAR BASALT;
THIN SECTION IS THOLEIITIC BASALT;
Piece No. : PCES 14A (110-113), 14B (114-121), 14C (122-130);
Alteration : FRAGMENT 14A HAS MOD RED TOP (5R5/4) WITH MOD
GREEN COATING;
Comments : GREYISH RED BASALT;
Vesicles : Size(mm): TO 15 Percent:
Location: Filling: QUARTZ, SMEC
Shape : IRREGULAR
VESICLES INFILLED WITH QUARTZ AND SMEC(?), ALL
HAVE CHARACTERISTIC BLACK LINING;
Groundmass : PLAGIOCLASE
PYROXENE
ID UNCERTAIN, PLAG AND PYX REDDENED;
Replacement: QUARTZ
SMECTITE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 579.00
Core: 46 Top of Core Depth (m) : 571.50
Sect: 5 Top of Section Depth(m): 577.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 46-4;
Piece No. : PCES 1 (0-5), 2 (5-13), 3 (13-20), 4 (20-27),
5 (27-35), 6 (35-41), 7 (44-50), 8 (51-57),
9 (57-60), 10 (61-67), 11 (67-73), 12 (73-83),
13 (86-90), 14 (91-95), 15 (96-105), 16 (105-110),
17 (110-118), 18 (118-125), 19 (125-130),
20 (130-140), 21 (140-149);
Texture : GNDMASS FINER IN SIZE IN BANDED AREAS;
Structure : PCES 20+21 SHOW DISTINCT LIGHT GREY (N7) BANDS FREE
OF VESICLES INCLINED AT 50 DEGREES, INTERVENING
BANDS SHOW VESICLES ORIENTED AT SAME ANGLE, IN PCE
21 ONE BAND IS NEAR VERTICAL AND MAY BE RELATED TO
GAS STREAMS IN 46-6;
Alteration : REDDENED GNDMASS IS PROBABLY ALTERED, BANDING
BELOW PCE 13 HIGHLY ALTERED BY BLACK/DARK GREEN
GRAIN;
Comments : GREYISH RED (10R4/2), PCE 18 SHOWS DISTINCT FLOW
BANDING BETWEEN TWO PARTLY ASSIMULATED "VESICULAR
CLASTS", AT PCE 13 APPROXIMATE LIMIT OF DOWNWARD
REDDENING (GRADATIONAL), BELOW PCE 13 MEDIUM GREY
AND GNDMASS DISTINCTLY FLOW BANDED, PROBABLY NO
COMPOSITIONAL DIFFERENCE BETWEEN REDDENED BASALT AND
GREY BASALT BELOW;
Vesicles : Size(mm): TO 15 Percent:
VESICLES OF ALL SIZES PERSIST THROUGHOUT AND ARE
BOTH OPEN AND FILLED, FILLING IS GREYISH BLACK(N7)
WITH LIGHT OLIVE GREY (5Y6/1) CORE, SMALLER
VESICLES ARE CONCENTRATED AND MAY BE RESIDUALS
FROM "VESICULAR CLASTS", OBVIOUS VESICLE CLASTS
ARE PRESENT THROUGHOUT BELOW PCE 6, PCES 20+21
SHOW ALTERNATING VESICLE FREE AND VESICULAR BANDS;
Groundmass : PLAGIOCLASE
Leg : 81 Top/Bottom Interval(mm): 0/ 510 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 579.51
Core: 46 Top of Core Depth (m) : 571.50
Sect: 6 Top of Section Depth(m): 579.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 46-5;
Piece No. : PCES 1 (0-10), 2 (9-20), 3 (21-33), 4 (33-45),
5 (46-51);
Texture : THE VESICLE FREE BASALT IS FINER-GRAINED TOWARDS ITS
CONTACT WITH THE VESICLE RICH SEGMENTATION AND
BECOMES COARSER TOWARDS ITS CENTER;
Structure : DOWN TO 15CM IN PCE 2 VESICLES ARE HORIZONTALLY
BANDED AND SEPARATED BY BANDS (N5) CONTAINING FEWER
VESICLES, VESICLE RICH BANDS ALSO DIFFER IN
POPULATION, BELOW 22CM (3-5) THERE IS A SPECTACULAR
VERTICAL STRUCTURE, IT CONSISTS OF ALMOST VESICLE
FREE MEDIUM LIGHT GREY (N6) BASALT SEPARATING ZONES
IN WHICH VESICLES (1MM) ARE HIGHLY CONCENTRATED,
FOLIATION IS ALSO PRESENT;
Comments : MEDIUM GREY(N5) BASALT, PROBABLY TWO PHASES PRESENT,
PHASE 1-VESICULAR BASALT THEN MAGMA STREAMED UPWARD
FROM BELOW;
Vesicles : VESICULAR, BELOW 15CM THE BASALT CONTAINS SPARSE
MINOR VESICLES;
Size(mm): 1 Percent:
BELOW 22CM ZONES OF 1MM VESICLES, HIGHLY
CONCENTRATED;
Groundmass : PLAGIOCLASE
PYROXENE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1480 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 581.98
Core: 47 Top of Core Depth (m) : 580.50
Sect: 1 Top of Section Depth(m): 580.50
LITHOLOGY: VESICULAR BASALT;
THIN SECTION-THOLEIITIC BASALT;
Piece No. : PCES 1A (0-10), 1B (10-19), 1C (19-35), 2A (38-44),
2B (45-52), 2C (51-62), 2D (62-73), 2E (73-96),
2F (97-127), 3 (130-144);
Texture : PHYRIC, VERTICAL CHANGES IN GRAIN SIZE BETWEEN PCES
1A AND 1B, SUGGESTION OF DECREASE IN GRAIN SIZE
TOWARD VESICLES, GNDMASS HAS TRACHYTIC TEXTURE
COMPOSED OF ELONGATED PLAG LATHS COMMON, VESICULAR
CLASTS- COARSE GNDMASS OF PLAG LATHS AND PYX,
VESICULAR CLASTS APPEAR IN PCE 1E, PRINCIPAL
DIFFERENCE FROM OVERLYING 35CM IS AN INCREASE IN THE
SIZE AND ABUNDANCE OF VESICULAR CLASTS, FILAMENTS OF
ORIENTED DARK MINERAL GRAINS, FLOW STRUCTURES
PRESENT, THERE IS A SUGGESTION OF FLOWAGE BETWEEN
CLASTS, THERE IS A SUGGESTION THAT THE VESICULAR
CLASTS MAY BE SEPARATED BY SUBVERTICAL FLOW
STRUCTURES;
Structure : IN PCES 2B+2C A 3MM VEIN PARTIALLY INFILLED WITH
MATRIX AND LINING OF GREYISH RED (5R4/2), VERTICAL
STRUCTURES REVEALED AS FILAMENTS OF ORIENTED DARK
MINERAL GRAINS- COMMON IN THE UPPER PART BUT BECOMES
RANDOM WITH DEPTH, VEIN AT 117CM IS INFILLED BY LIGH
BLUISH GREY (5B7/1) MEDIUM GREY MINERAL (CALCITE?),
REDDENED VEIN SUB-HORIZONTAL, VESICULAR CLASTS HAVE
RARE EVIDENCE OF TRACHYTIC STRUCTURE;
Alteration : REACTION RIMS ARE COMMON AROUND THE CLASTS BUT
THE SMALLER ONES SHOW PARTIAL ASSIMULATION,
REDDENING (5R4/2) ASSOCIATED WITH THE HOST ROCK
AND THE GREYISH BLUE VEIN AT 89CM EVIDENT, HOST
BASALT AS WELL AS VEIN REDDENED (5R4/2);
Vesicles : Size(mm): TO 7 Percent:
PCES 1A-1C TRAINS OF VERTICALLY ELONGATED FILLED
AND OPEN VESICLES UP TO 7MM IN LENGTH AND
VERTICAL CHANGES DEFINED ALSO BY MARKED CHANGE
IN VESICULARITY;
Size(mm): TO 10 Percent:
Location: Filling: SMEC, QUARTZ,
Location: Filling: CALCITE
IN PCES 1A-1C FLOW STRUCTURES ARE ALSO PRESENT
WITH OPEN VESICLES UP TO 1CM, VESICLES TYPICALLY
HAVE BLACK LINING (SMEC) AND LINED (OPEN) OR
INFILLED WITH MEDIUM GREY (N5)- QUARTZ OR CALCITE,
SEVERAL LARGE VESICLES (4CM) INFILLED WITH GREYISH
BLUE GREEN (5BG5/2) PRESENT;
Size(mm): TO 5 Percent:
IN PCE 2F, LARGE OPEN VESICLES (TO 0.5CM) COMMON
IN THE MATRIX BETWEEN "CLASTS" ESPCIALLY WITHIN
CLASTS;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
Replacement: SMECTITE
QUARTZ
CALCITE
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 583.50
Core: 47 Top of Core Depth (m) : 580.50
Sect: 2 Top of Section Depth(m): 582.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 47-1, THE SAME LITHOLOGY OBSERVED IN
LOWER PART OF CORE 47-1;
Piece No. : PCES 1A (0-10), 1B (14-25), 1C (26-35), 1D (35-45),
1E (44-55), 2A (58-75), 2B (75-83), 3 (86-101),
4A (103-104), 4B (104-110), 4C (113-115),
5 (114-119), 6A (121-138), 6B (139-145);
Texture : PREDOMINANT PLAG LATHS SHOW PRONOUNCED TRACHYTIC
TEXTURE, PCE 4A IS COARSER PLAG/PYX AND NO TRACHYTIC
TEXTURE, IN PCES 6A-B VESICULAR CLASTS (5-0.5CM) AND
OLIVE GREY FILAMENTS ARE VERTICAL TO SUB-VERTICAL;
Structure : VERTICAL FILAMENTS ARE EVIDENT BETWEEN 35-54CM BUT
ARE REPLACED DOWN SECTION BY FILAMENTS DIPPING AT 50
DEGREES, VEINS SHOW A LIGHT BLUISH GREY (5B7/1)
OLIVE GREY FILAMENTS ARE VERTICAL TO SUB-VERTICAL,
VEINS SHOW A LIGHT BLUISH GREY (5B7/1) INFILL-
INFILL CALCITE (?);
Alteration : REDDENING ASSOCIATED WITH SUB-HORIZONTAL VEINS AND
DIFFUSION INTO THE GNDMASS IS EVIDENT, THE TOP OF
A VESICULAR CLAST AT 30CM HAS BEEN REDDENED,
IRREGULAR BLACK PATCHES AND LIGHT OLIVE GREY
PATCHES;
Comments : MEDIUM LIGHT GREY (N6), CONTACT AT PCE 4A, PCES
6A-B ARE MEDIUM LIGHT GREY (N6), POSSIBILITY THAT
PCE 4 OR PCE 5 MAY BE WRONG WAY UP;
Vesicles : Size(mm): 50 Percent:
IN PCE 4A 5CM DIAMETER VESICLE HAS GREYISH BLACK
(N2) IRREGULAR LINING OF 5CM DIAMETER VESICLE,
CRYSTALS(?) LINING VESICLES SEEM TO BE COATED
BLACK WITH LIGHT GREY CORE, A SECOND 3CM LONG OPEN
VESICLE OCCURS ON THE OUTSIDE OF THE CORE;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
Replacement: QUARTZ
CALCITE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 585.00
Core: 47 Top of Core Depth (m) : 580.50
Sect: 3 Top of Section Depth(m): 583.50
LITHOLOGY: VESICULAR BASALT;
THIN SECTION- THOLEIITIC BASALT;
Piece No. : PCES 1A (0-15), 1B (15-61), 2A (61-75), 2B (75-85),
3A (86-92), 3B (91-97), 4A (98-117), 4B (117-133),
5 (134-147);
Texture : PHYRIC, TRACHYTIC TEXTURE, IN PCE 3B 1CM ZONE OF
FINE-GRAINED NEARLY VESICLE FREE BASALT VERTICAL AND
NEARLY 5CM IN LENGTH, GNDMASS PREDOMINANTLY PLAG
LATHS SHOWING TRACHYTIC TEXTURE, SEVERAL CLASTS- THE
LARGER ONES SHOW A DISTINCTIVE GRADED STRUCTURE AS
SHOWN BY THE BLACK PATCHES, THE DOMINANT FEATURE IS
THE UBIQUITOUS PRESENCE OF VERTICAL TO NEAR VERTICAL
FILAMENTS OF DARK MINERALS SHOWN ALSO BY THE
TRACHYTIC TEXTURE, PYX ALSO ORIENTED INTO FILAMENTS,
ZONE OF FINE-GRAINED NEARLY VESICLE FREE BASALT IN
PCE 3B TRUNCATED DOWNWARDS BY AN IRREGULAR OLIVE
GREY PATCH (5Y4/1);
Comments : MEDIUM GREY (N5);
Vesicles : VESICULAR, VESICULAR CLASTS RANGING IN SIZE FROM
1-6CM OR LESS OCCUR COMMONLY THROUGHOUT, OPEN AND
INFILLED VESICLES OCCUR THROUGHOUT, VESICLE FREE
ZONE IN PCE 3B;
Groundmass : PLAGIOCLASE
PREDOMINANTLY PLAG LATHS SHOW TRACHYTIC TEXTURE;
PYROXENE
ORIENTED INTO FILAMENTS;
Leg : 81 Top/Bottom Interval(mm): 0/ 880 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 585.88
Core: 47 Top of Core Depth (m) : 580.50
Sect: 4 Top of Section Depth(m): 585.00
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1A (2-15), 1B (15-22), 1C (22-30), 2A (31-45),
2B (40-44), 3 (40-55), 4 (52-56), 5A (57-62),
5B (62-76), 5C (75-84), 6 (86-88);
Texture : PHYRIC, SUBTLE DECREASE IN GRAIN SIZE, BELOW 40CM
VESICLE CLASTS BECOME SMALLER AND SEEM TO BE MORE
ASSIMULATED BY THE GNDMASS, VESICULAR CLASTS DECREAS
IN SIZE AND ABUNDANCE BELOW- GRADING CLEAR IN
CLASTS;
Structure : BELOW- GRADING CLEAR IN SEVERAL CLASTS, VERTICAL
STRUCTURES BECOME RARE;
Comments : MEDIUM GREY (N5), BASALT CONTACT AT 79CM, BASE OF
UNIT BETWEEN 5C AND 6;
Vesicles : VESICULAR, VESICLES DECREASE IN SIZE, LARGE OPEN
VESICLES ARE ABSENT BELOW 40CM AND SMALL IRREGULAR
FILLED VESICLES ARE MORE ABUNDANT THOUGH
CONCENTRATED IN IRREGULAR PATCHES;
Size(mm): 0.5-1 Percent:
FINE INFILLED VESICLES (0.5MM, BLACK N2) GRADE
DOWN INTO OPEN VESICLES (1MM), OPEN AND INFILLED
VESICLES HAVE PALER CORES;
Leg : 81 Top/Bottom Interval(mm): 910/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 586.50
Core: 47 Top of Core Depth (m) : 580.50
Sect: 4 Top of Section Depth(m): 585.91
LITHOLOGY: SCORIACEOUS BASALT;
Piece No. : PCES 7 (91-94), 8 (95-107), 9 (110-118),
10 (120-130), 11 (137-144);
Texture : SEVERAL LARGE LITHIC CLASTS IN FINER GROUNDMASS;
Structure : DARK RED (5R4/2) PATCHES;
Comments : SCORIACEOUS LAVA, PCE 10 IS VERY DUSKY RED (10R2/2)
WITH VERY DARK RED (5R2/6) PATCHES;
Vesicles :
Location: Filling:
Shape : ELONGATE
EXTREMELY VESICULAR IN PATCHES, VESICLES
ELONGATE (SUB-HORIZONTAL FLATTENING?), SPARSE TO
RARE DUSKY GREEN (5G3/2) INFILLS VESICLES, CLASTS
DIFFER IN VESICULARITY;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 589.00
Core: 48 Top of Core Depth (m) : 587.50
Sect: 1 Top of Section Depth(m): 587.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1A (0-11), 1B (11-28), 1C (28-37), 1D (38-42),
2 (42-48), 3A (49-51), 3B (51-62), 3C (62-76),
3D (76-85), 3E (85-92), 4 (95-97), 5 (99-100),
6A (102-135), 6B (135-150);
Texture : PHYRIC, PLAG LATHS WITH SMALLER GRAINS OF PYX(?)
LOCALLY CONCENTRATED INTO IRREGULAR LENSOID
TRACHYTIC TEXTURE SPARSE TO CORE;
Structure : INTERVAL (102-150) HAS HORIZONTAL STREAKS TOWARDS
BASE OF 6A AND SPARSELY IN 6B;
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): 0.3 Percent:
INTERVAL (0-12): VESICLES RANGE IN SIZE FROM 0.3MM
DOWN AND ARE OPEN AND FILLED, OPEN VESICLES LINED
WITH LIGHT GREY (N5) AND BLACK (N6) WHICH IS ALSO
SEEN IN FILLED VESICLES;
Size(mm): 1 Percent:
Location: Filling: QUARTZ, CALCITE
INTERVAL (37-100): VESICLES DECREASE IN ABUNDANCE
BY 50% COMPARED TO ABOVE, MAXIMUM SIZE 0.7CM,
SOME VESICLES INFILLED WITH GREYISH YELLOW (5Y8/4)
AND VERY LIGHT GREY (N8)- QUARTZ AND CALCITE(?)
OTHERWISE VESICLES GENERALLY CLOSED WITH BLACK
INFILL, VESICLES IN PCE 3D APPARENTLY INCLINED AT
60 DEGREES, BLACK INFILL TO VESICLES UNDER
BINOCULAR COMMONLY HAS DUSKY GREEN CORE OFTEN WITH
COMPLETELY WHITE FILIGREE STRUCTURE;
Size(mm): 10 Percent:
IN INTERVAL (100-150) VESICLES SPARSE AND ABOUT
1CM IN DIAMETER, TYPICALLY VERY LIGHT GREY (N8)
CORE AND BLACK LINING;
Groundmass : PLAGIOCLASE
PREDOMINANTLY PLAG LATHS;
PYROXENE
SMALL GRAINS OF PYX(?), PLAG AND PYX LOCALLY
CONCENTRATED INTO IRREGULAR LENSOID TRACHYTIC
TEXTURE SPARSE TO RARE;
Replacement: QUARTZ
CALCITE
ID UNCERTAIN;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 590.50
Core: 48 Top of Core Depth (m) : 587.50
Sect: 2 Top of Section Depth(m): 589.00
LITHOLOGY: BASALT;
THIN SECTION THOLEIITIC BASALT, CONTINUED FROM 46-1;
Piece No. : PCES 1 (0-20), 2A (21-36), 2B (31-42), 3A (44-61),
3B (59-65), 3C (65-116), 4 (117-133), 5 (135-145);
Texture : PHYRIC, VESICLE CLASTS ARE SPARSE TO RARE;
Structure : PRINCIPAL VARIATION IS THE CONTINUED (FROM 48-1)
DECREASE IN VEINS, AT 60CM VEINS ARE INCLINED AT 50-
60 DEGREES, CHANGE IN VESICLE ABUNDANCE IS MORE OR
LESS COINCIDENT WITH AN INCREASE IN PROMINENCE OF
LATE STAGE FRACTURING-THESE ARE INCLINED AT HIGH
ANGLE OR ARE HORIZONTAL-THE CHANGE FROM ONE TO THE
OTHER IS ABRUPT (FOR EXAMPLE 99CM), SMALL VEINS
(SUB-HORIZONTAL AND PARALLEL FRACTURES) ARE INFILLED
WITH A BLACK (N6) MINERAL BUT A LARGE VEIN (2CM) IN
PCE 3C HAS A BLACK LINING AND IS COLOR BANDED FROM
YELLOWISH GREY (5Y8/1) TO LIGHT GREENISH GREY
(5G8/1) TOWARDS THE CENTER, BOTH BOUNDARIES ARE
SHARP, THE BLACK LININGS APPEAR TO HAVE INGROWN INTO
THE INNER YELLOWISH GREY CORE;
Comments : MEDIUM GREY (N5) BASALT, REDDENED ZONE (RARE RED
5R6/2) AT INTERVAL (15-25);
Vesicles : Size(mm): 5 Percent:
BELOW 60CM ONLY SPARSE LARGE (0.5CM) VESICLES ARE
PRESENT, THE CHANGE IS MORE OR LESS COINCIDENT
WITH AN INCREASE IN PROMINENCE OF LATE STAGE
FRACTURES;
Groundmass : PLAGIOCLASE
PYROXENE
IN REDDENED ZONE PLAG AND PYX CONCENTRATED IN
PATCHES, RED MINERAL GRAINS (ALTERED PYX) ACCOUNT
FOR THE RED COLOR, OUTSIDE THE REDDENED ZONE THE
GROUNDMASS CONSISTS OF PLAG AND PYX CONCENTRATED
IN SMALL IRREGULAR PATCHES CONCENTRATED IN THIN
LAYERS;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 592.00
Core: 48 Top of Core Depth (m) : 587.50
Sect: 3 Top of Section Depth(m): 590.50
LITHOLOGY: APHYRIC BASALT;
CONTINUED FROM 48-2;
Piece No. : PCES 1A (0-48), 1B (48-150);
Texture : APHYRIC, TRACHYTIC TEXTURE SPARSE;
Structure : ONE PRINCIPAL VARIATION IS THE ATTITUDE OF THE
FRACTURES, VEINS TYPICALLY INFILLED WITH BLACK (N2)
MINERAL;
Alteration : A FAINT REDDENING IS PRESENT ABOVE THE VESICULAR
ZONE, DIFFUSE RED COLOR (GROUNDMASS- SPARSE RED
MINERAL-ALTERED PYX ?);
Vesicles : ONE PRINCIPAL VARIATION IS THE PRESENCE OF A ZONE
OF ABUNDANT VESICLES (BLACK OR BLACK-LIGHT GREY N2
CORE);
Groundmass : PLAGIOCLASE
PREDOMINANTLY PLAG LATHS;
PYROXENE
SPARSE RED MINERAL-ALTERED PYX(?), PLAG AND PYX
TYPICALLY CONCENTRATED WITHIN STREAKS;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 593.50
Core: 48 Top of Core Depth (m) : 587.50
Sect: 4 Top of Section Depth(m): 592.00
LITHOLOGY: BASALT;
CONTINUED FROM 48-3;
Piece No. : PCES 1 (0-22), 2 (22-119), 3 (120-147);
Structure : UBIQUITOUS ARE SUB-HORIZONTAL TO HORIZONTAL BLACK
LAMINAE COMPOSED OF PYX;
Alteration : INTERVAL (14-36) IS REDDENED (10R6/2), GROUNDMASS
INCLUDES DIFFUSED PATCHES OF RED AND DISCRETE
GRAINS OF A RED MINERAL (ALTERED PYX ?), TOP OF
INTERVAL IS A DIFFUSED BOUNDARY AND BOTTOM OF
INTERVAL IS A RELATIVELY SHARP BOUNDARY;
Comments : BASALT IS MEDIUM GREY (N5);
Vesicles : VESICLES ARE SPARSE TO COMMON AT INTERVAL (10-30)
AND SPARSE TO 115CM AND SPARSE TO COMMON BELOW;
Size(mm): 10-30 Percent:
AT INTERVAL (10-30), SLIGHTLY LARGER IN MEAN SIZE
THAN THOSE AT THE BASE;
Groundmass : PLAGIOCLASE
EQUIGRANULAR LATHS;
PYROXENE
PYX IS CONCENTRATED IN STREAKS;
Leg : 81 Top/Bottom Interval(mm): 0/1410 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 594.91
Core: 48 Top of Core Depth (m) : 587.50
Sect: 5 Top of Section Depth(m): 593.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 48-4, THIN SECTION-THOLEIITIC BASALT;
Piece No. : PCES 1 (1-20), 2A (21-26), 2B (25-62), 2C (60-75),
2D (75-92), 2E (92-123), 2F (124-131), 3 (133-141);
Texture : PHYRIC;
Structure : HORIZONTAL TO SUB-HORIZONTAL FRACTURES WITH PYX
STREAKED OUT ALONG THEM OCCUR THROUGHOUT;
Comments : MEDIUM GREY (N5) BASALT;
Vesicles : Size(mm): 0.5-150 Percent:
VESICLES OCCUR THROUGHOUT;
Groundmass : PLAGIOCLASE
PREDOMINANTLY PLAG LATHS;
PYROXENE
PYX GRAINS SMALLER THAN PLAG LATHS, PYX GRAINS
CONCENTRATED IN DARKENED LAYER(?), IN VARIETY OF
DARK LAYERS THERE IS A SUGGESTION OF PREFERRED
ORIENTATION OF PLAG LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/1360 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 596.36
Core: 48 Top of Core Depth (m) : 587.50
Sect: 6 Top of Section Depth(m): 595.00
LITHOLOGY: BASALT;
CONTINUED FROM 48-5;
Piece No. : PCES 1A (0-10), 1B (10-20), 1C (20-51), 1D (50-62),
2 (64-72), 3 (73-81), 4A (83-91), 4B (88-106),
4C (105-120), 5 (122-135);
Texture : PHYRIC, VESICLE CLASTS;
Structure : THE PRINCIPAL VARIATION IS IN THE ATTITUDE OF THE
FRACTURES WHICH ARE SUB-HORIZONTAL AT INTERVAL(0-25)
AND 50 DEGREES AT INTERVAL (63-70) AND 70 DEGREES AT
INTERVAL (70-130), PCE 2 IS SLICKENSIDED;
Alteration : VESICLE CLASTS SHOW VARYING DEGREES OF REACTION
WITH THE GROUNDMASS;
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): <0.5 Percent:
SMALL AND SPARSE TO RARE THROUGHOUT THE SECTION,
VESICLE CLASTS (UP TO 3CM) OCCUR SPORADICALLY;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
SUBORDINATE, THERE IS SUGGESTION THAT PLAG LATHS
MAY BE ORIENTED PERPENDICULAR TO THE HORIZONTAL
STREAKS OF PYX(?);
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 598.00
Core: 49 Top of Core Depth (m) : 596.50
Sect: 1 Top of Section Depth(m): 596.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 48-6, DOWN TO 80CM THERE ARE MAJOR
VARIATIONS IN LITHOLOGY;
Piece No. : PCES 1A (2-5), 1B (5-18), 1C (18-27), 1D (27-37),
1E (37-45), 1F (45-54), 1G (54-71), 1H (71-82),
1I (81-87), 2A (89-106), 2B (105-109), 2C (109-145);
Texture : PHYRIC, VESICLE CLASTS UP TO 1CM OCCUR SPORADICALLY,
Structure : BLACK PATCHES OF PYX SHOW A RANDOM TO RARE SUB-
HORIZONTAL ORIENTATION, THE BASE OF THIS INTERVAL IS
DEFINED BY A 2MM DARK GREY BAND NEAR 80CM, BETWEEN
90+106CM A SERIES OF 3MM MEDIUM GREY (N5) AND
MEDIUM DARK GREY (N4) BANDS ARE PRESENT, BELOW THIS
LEVEL THE DARK BANDS ARE ORIENTED VERTICALLY BUT
CROSS CUT INCLINED (10 DEGREES) BANDS NEAR THE BASE;
Comments : BELOW 80CM THE VESICLE CLASTS ARE MORE ABUNDANT AND
LARGER SHOWING SHARP AND DIFFUSE CONTACTS WITH THE
MATRIX;
Vesicles : Size(mm): TO 2 Percent:
VESICLE CLASTS UP TO 1CM OCCUR SPORADICALLY,
BELOW 80CM VESICLE CLASTS ARE MORE ABUNDANT AND
LARGER (2CM), VESICULAR;
Groundmass : PLAGIOCLASE
PYROXENE
LOCALLY SHOWING A STRONG PREFERRED ORIENTATION
PARALLEL OR PERPENDICULAR TO THE PYX STREAKS, JUST
ABOVE THE CONTACT AT 80CM BINOCULAR EXAM SHOWS A
STRONG PREFERRED ORIENTATION OF THE PLAG AND PYX;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 599.50
Core: 49 Top of Core Depth (m) : 596.50
Sect: 2 Top of Section Depth(m): 598.00
LITHOLOGY: BASALT;
CONTINUED FROM 49-1;
Piece No. : PCES 1A (0-18), 1B (16-28), 2 (29-33), 3 (36-38),
4A (41-61), 4B (60-70), 4C (70-74), 4D (74-90),
4E (89-100), 4F (97-120), 5 (121-145);
Texture : PHYRIC, VESICLE CLASTS (UP TO 1CM) OCCUR SPARSELY
THROUGH THE SECTION;
Structure : ABUNDANCE OF DARKER (5Y4 1) HORIZONTAL LAYERS;
Comments : MEDIUM GREY (N5), THE PRINCIPAL VARIATION IS A
SUBTLE VARIATION IN COLORS FROM MEDIUM GREY (N5)
TOWARDS MEDIUM DARK GREY (N4) REFLECTING THE
ABUNDANCE OF THE DARKER (5Y4/1) HORIZONTAL LAYERS;
Vesicles : Size(mm): <0.5 Percent:
VESICLES ARE SMALL AND MINOR;
Groundmass : PLAGIOCLASE
PYROXENE
MINOR, CONCENTRATED IN THE DARKER LAYERS, SOME
EVIDENCE OF VERTICAL STREAKING OF THE PYX IN 1A;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 601.00
Core: 49 Top of Core Depth (m) : 596.50
Sect: 3 Top of Section Depth(m): 599.50
LITHOLOGY: BASALT;
CONTINUED FROM 49-2, SAME AS 49-2;
Piece No. : PCES 1A (1-31), 1B (31-79), 1C (78-150);
Texture : VESICLE CLASTS SPARSE AND TYPICALLY WITHOUT
REACTION RIMS;
Structure : ONLY SIGNIFICANT DIFFERENCE FROM 49-2 IS TENDENCY
FOR PYX TO BE CONCENTRATED IN 3MM LAYERS OF
HORIZONTAL TO SUB-HORIZONTAL ALTITUDES DOWN CORE,
VESICLE CLASTS SPARSE AND TYPICALLY WITHOUT
REACTION RIMS, 2MM SMEC VEIN WITH THIN STREAKS OF
LIGHT GREY (N7)-CALCITE(?);
Groundmass : PLAGIOCLASE
PYROXENE
SUGGESTION THAT LATHS AND LONG AXES OF DARK
LAYERS ARE ORIENTED PERPENDICULAR TO THE DARKER
LAYERS WHICH APPEAR DIFFERENT (SMALLER?) IN GRAIN
SIZE THAN IN INTERVENING GROUNDMASS;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 602.50
Core: 49 Top of Core Depth (m) : 596.50
Sect: 4 Top of Section Depth(m): 601.00
LITHOLOGY: BASALT;
CONTINUED FROM 49-3;
Piece No. : PCES 1A (1-15), 1B (15-66), 1C (66-95), 1D (95-150);
Texture : PHYRIC, SPARSE VESICLE CLASTS UP TO 1CM SIZE;
Structure : OCCASIONAL 1MM VEINS INFILLED WITH SMEC ARE PRESENT,
HORIZONTAL TO SLIGHTLY INCLINED BANDS OF PYX OCCUR
THROUGHOUT, THE MOST PROMINENT FEATURE IS THE 1CM
WIDE VEIN IN PCE (1C) INCLINED AT APPROXIMATELY 70
DEGREES, GREYISH BLACK (N7) VEIN LINING ALSO
PENETRATES HOST ROCK, BLACK VEIN LINING CONTAINING
LIGHT GREY (N6) AND DUSKY GREEN PATCHES THAT
PENETRATE MAIN VEIN FILLING, SPARSE DUSKY RED
PATCHES PRESENT;
Comments : MEDIUM GREY(N5);
Vesicles : VESICLES SPARSE THROUGHOUT;
Groundmass : PLAGIOCLASE
PLAG LATHS PREDOMINATE;
PYROXENE
PYX CONCENTRATED IN IRREGULAR PATCHES OR
HORIZONTAL TO SUB-HORIZONTAL LAYERS;
Replacement: SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/1250 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 603.75
Core: 49 Top of Core Depth (m) : 596.50
Sect: 5 Top of Section Depth(m): 602.50
LITHOLOGY: BASALT;
CONTINUED FROM 49-4;
Piece No. : PCES 1A (1-30), 1B (30-45), 1C (45-63), 1D (63-75),
1E (76-125);
Texture : PHYRIC, PRINCIPAL TEXTURE OF THE SECTION IS THE
BRAIDED VEIN STRUCTURE BETWEEN 95 & 124CM, SPARSE
TRACHYTIC TEXTURE;
Structure : PRINCIPAL VARIATION IS IN ABUNDANCE OF DARK STREAKS
WHICH INCREASE INTO LOWER PART OF THE SECTION WHICH
IS CLOSER TO MEDIUM DUSKY GREY (N4), BRAIDED VEIN
STRUCTURE BETWEEN 95 & 124CM, ONE 4MM THICK AND ONE
1MM THICK VEIN ARE PARALLEL AND INCLINED AT 70
DEGREES, THE VEINS CUT AND TRUNCATE EARLIER VEINS
PARALLEL TO THE FOLIATION IN THE BASALT, INCLUDED
WITH BLACK (N2) INFILL OF THE VEIN ARE 3CM ANGULAR
FRAGMENTS OF MEDIUM GREY (N5) BASALT, THIS PRESENCE
AND A SUGGESTION OF SLICKENSIDES IN THE FACE OF ONE
OF THE VEINS SUGGESTS A SMALL FAULT;
Comments : MEDIUM GREY (N5);
Groundmass : PLAGIOCLASE
PYROXENE
Leg : 81 Top/Bottom Interval(mm): 0/ 780 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 604.78
Core: 49 Top of Core Depth (m) : 596.50
Sect: 6 Top of Section Depth(m): 604.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 49-5;
Piece No. : PCES 1A (2-33), 1B (33-78);
Texture : PHYRIC, NO DOWNWARD CHANGE IN GRAIN SIZE APPARENT;
Structure : THE PRINCIPAL FEATURE IS THE COMPLEX SYSTEM OF
FRACTURES EXTENDING THE LENGTH OF 1A AND 1B, THE
FRACTURES HAVE A VEIN INFILLING RANGING FROM BLACK
(N2) TO BLACK WITH LIGHT OLIVE BROWN PATCHES
(2.5Y5/6) AND LIGHT GREY (N7) INFILLING, ANGULAR AND
RUPTURED BASALT FRAGMENTS OCCUR THROUGHOUT THE
LENGTH OF THE VEIN, HORIZONTAL VEIN IN THE HOST
BASALT TRUNCATE AGAINST THE VEIN, FAULT CONTINUES
INTO TOP OF NEXT FLOW UNIT WHERE IT IS SEEN IN THE
SCORIACEOUS TOP OF THE UNDERLYING UNIT;
Comments : MEDIUM GREY (N5), FLOW UNIT BOUNDARY AT 78CM;
Vesicles : PRINCIPAL FEATURE IS AN INCREASE IN VESICLE SIZE
AND ABUNDANCE TOWARDS THE BASE OF THE UNIT;
Groundmass : PLAGIOCLASE
PYROXENE
PLAG LATHS AND PYX WITHOUT PREFERRED ORIENTATION;
Leg : 81 Top/Bottom Interval(mm): 780/1250 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 605.25
Core: 49 Top of Core Depth (m) : 596.50
Sect: 6 Top of Section Depth(m): 604.78
LITHOLOGY: SCORIACEOUS BASALT;
Piece No. : PCES 2 (7-85), 3 (85-90), 4A (91-96), 4B (96-105),
5 (107-125);
Texture : NUMEROUS ANGULAR LITHIC FRAGMENTS IN THE GRNDMASS;
Structure : DUSKY BLUE (5PB/2) DEFORMED LAYER RESTING IN DARK
GREY (N3) OF LAPILLI PASSING DOWN INTO (4A-B),
SCORIACEOUS TOP OF UNIT CONSISTING OF DARK GREY (N3)
AND DARK REDDISH BROWN (10R3/4) FRAGMENTS OF
VESICULAR BASALT SHOWING ALL GRADES BETWEEN THESE
EXTREMES;
Vesicles : EXTREMELY VESICULAR BASALT;
Size(mm): >1 Percent: 0
LARGE VESICLES (> 1CM) AND SMALL INFILLED VESICLES
CONTAIN LIGHT BLUE GREEN (3BG6/6) MINERAL, VESICLE
IN BASALT INFILLED WITH DUSKY BLUE GREEN (5BG3/2);
Leg : 81 Top/Bottom Interval(mm): 0/1340 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 606.84
Core: 50 Top of Core Depth (m) : 605.50
Sect: 1 Top of Section Depth(m): 605.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (0-15), 2 (17-21), 3 (25-28), 4 (30-33),
5 (35-39), 6 (42-43), 7 (47-50), 8 (52-55),
9 (57-60), 10 (62-65), 11 (68-72), 12 (75-77),
13 (80-83), 14 (86-88), 15 (90-92), 16 (94-97),
17 (100-104), 18 (106-110), 19 (111-112),
20 (115-118), 21 (121-133);
Texture : PHYRIC, GENERAL IMPRESSION OF INCREASING GRAIN SIZE
WITH DECREASING ABUNDANCE OF SMALL VESICLES;
Structure : PCES 1-3 HAVE SPLIT NATURALLY ALONG A SLICKENSIDED
SURFACE, SLICKENSIDES VERTICAL WITH PALE OLIVE
FIBROUS PATCHES ALSO SLICKENSIDED- NOT PRESENT BELOW
PCE 3, POSSIBLE FAULT;
Comments : MEDIUM GREY (N5) BASALT;
Vesicles : Size(mm): >5 Percent:
IN PCES 4-9 ABUNDANT LARGE OPEN VESICLES;
Size(mm): <0.5 Percent:
IN PCES 9-15, SHARP DECREASE IN ABUNDANCE OF
LARGE VESICLES AND SHARP INCREASE IN ABUNDANCE OF
SMALL VESICLES TO COMMON, TRANSITION IS IN PCE 9,
SMALL VESICLES ARE O.5CM OR LESS, LARGE VESICLES
UNFILLED, BOTH CONTAIN LIGHT GREY (N7) AND LIGHT
BLUE-GREEN (5BG6/6) IN LINING OF BLACK MINERAL;
Size(mm): 10 Percent:
IN PCES 16-21, DECREASE IN ABUNDANCE OF SMALL
VESICLES TO SPARSE, LARGE VESICLES STILL PRESENT
BUT LARGELY INFILLED, LIGHT GREY (N7) COMMON IN
LARGE VESICLES, LARGE VESICLE SIZE 1CM;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
SMALLER PYX GRAINS;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 608.50
Core: 50 Top of Core Depth (m) : 605.50
Sect: 2 Top of Section Depth(m): 607.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 50-1;
Piece No. : PCES 1A (0-50), 1B (50-87), 1C (87-150);
Texture : PHYRIC;
Structure : INTERVAL (13-27) ZONE OF ABUNDANT VESICLES
APPARENTLY STRATIFIED, AT 28CM VEIN(?) LINED WITH
BLACK- PREDOMINANTLY LIGHT GREY (N7) CORE WITH MINOR
OLIVE GREY (5Y7/1), FRACTURES VERTICAL IN PCE 1A, IN
PCE 1B ABUNDANT FRACTURES SPACED AT 1CM INTERVAL;
Comments : MEDIUM GREY (N5) BASALT, IN PCE 1A CLEAR CONTACT
WITH BASALT ABOVE AND BELOW LARGER IN GRAIN SIZE AND
SMALLER VESICLES THAN THE SMALLER SIZE ASSOCIATED
WITH THE LARGER VESICLES;
Vesicles : Size(mm): >5 Percent:
INTERVAL (13-27) ZONE OF ABUNDANT VESICLES,
LARGEST VESICLES (0.5CM) RANDOM BUT SMALLER
VESICLES CROWDED;
Size(mm): 15 Percent:
IN PCE 1B, NO SMALL VESICLES, SPARSE LARGE
VESICLES (1.5CM) HAVE BLACK LINING AND LIGHT
GREY (N7) CORE INTERGROWN WITH MINOR BLACK (N2);
Size(mm): 3 Percent:
AT 130CM SHARP BUT GRADUATED INCREASE IN VESICLE
SIZE, VESICLE MEAN SIZE 3CM;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
TENDENCY FOR PYX TO BE ORIENTED ALONG HORIZONTAL
PLANES;
Leg : 81 Top/Bottom Interval(mm): 0/ 370 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 608.87
Core: 50 Top of Core Depth (m) : 605.50
Sect: 3 Top of Section Depth(m): 608.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 50-2;
Piece No. : PCES 1A (0-31), 1B (31-37);
Texture : PHYRIC;
Comments : MEDIUM GREY (N5) BASALT, BASE OF FLOW UNIT;
Vesicles : Size(mm): 0.5-10 Percent:
VESICLE SIZE (0.5-10), INFILLED VESICLES RARE,
VESICLES TYPICALLY INFILLED WITH BLACK (N2) WITH
LIGHT GREY (N7) FLECKS;
Leg : 81 Top/Bottom Interval(mm): 390/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 610.00
Core: 50 Top of Core Depth (m) : 605.50
Sect: 3 Top of Section Depth(m): 608.89
LITHOLOGY: SCORIACEOUS BASALT;
Piece No. : PCES 2 (39-47), 3A (50-60), 3B (60-65), 3C (66-75),
4 (76-88), 5 (89-97), 6 (99-108), 7 (111-115),
8 (117-145);
Texture : GRNDMASS IS VERY FINE-GRAINED APHYRIC TO APHANITIC;
Structure : SCORIACEOUS;
Comments : BLACKISH RED (5R2/2), UPPER PART OF FLOW UNIT
EXTENDS TO BASE OF SECTION;
Vesicles : VESICLES LINED WITH DARK DUSKY GREEN (5BG3/2),
A DARK DUSKY GREEN (5BG3/2) TO LIGHT GREYISH
GREEN (5BG5/2) MINERAL TYPICALLY LINES MANY OF THE
SMALL VESICLES, IMPRESSION IS OF A DECREASE IN
VESICLE SIZE DOWNWARD;
Leg : 81 Top/Bottom Interval(mm): 0/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 615.97
Core: 51 Top of Core Depth (m) : 614.50
Sect: 1 Top of Section Depth(m): 614.50
LITHOLOGY: BASALT;
Piece No. : PCES 1 (0-20), 2 (20-27), 3 (28-37), 4 (37-46),
5 (47-54), 6A (55-59), 6B (60-86), 6C (86-98),
6D (98-110), 6E (110-121), 6F (121-132),
6G (131-147);
Texture : PHYRIC, COMPLEX FLOW STRUCTURE IN VESICLE
ORIENTATION;
Structure : IN PCE 1 VEIN WITH HORIZONTAL SLICKENSIDES AND
FIBROUS CALCITE-BLACK MINERAL IS SAPONITE, A
PRINCIPAL VARIATION DOWN SECTION IS THE APPEARANCE
OF THE CHARACTERISTIC SUBHORIZONTAL FOLIATION, IN
PCE 6F CALCITE VEIN (FIBERS PERPENDICULAR TO VEIN
EDGE), VEIN INCLINED AT 80 DEGREES BUT LATE STAGE
FRACTURE NOT DISPLACED ALTHOUGH SLICKENSIDES
PRESENT;
Comments : MEDIUM GREY (N5), CONTACT BETWEEN BASALT WITH
VESICLE FLATTENED PARALLEL TO FOLIATION AND BELOW
ZONE SHOWING COMPLEX FLOW STRUCTURE;
Vesicles : IN PCE 4 LIGHT GREY (N7) YELLOWISH (5Y8/1)
VESICLE INFILL, APART FROM THE ZONES OF INCLINED
VESICLES AND THE FOLIATION DOWN SECTION IS A
DECREASE IN THE ABUNDANCE OF VESICLES, IN PCE 6B
VESICLES INCLINED AT 40 DEGREES, VESICLES
PREDOMINANTLY BLACK (N2) WITH LIGHT GREY (N7)
CORES;
Replacement: CALCITE
SAPONITE
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 617.50
Core: 51 Top of Core Depth (m) : 614.50
Sect: 2 Top of Section Depth(m): 616.00
LITHOLOGY: BASALT;
Piece No. : PCES 1A (0-22), 1B (22-32), 2A (41-45), 2B (46-82),
2C (82-101), 2D (100-120), 2E (121-150);
Texture : PHYRIC;
Structure : PREDOMINANT VARIATION DOWN CORE IS IN THE ABUNDANCE
& INCLINATION OF THE LATE STAGE FRACTURE FOLIATION,
IN PCE 1A THE FOLIATION IS SUBHORIZONTAL AND CONSIST
OF DISCRETE 1-2MM WIDE MEDIUM DARK GREY (N4)
BANDS COMPOSED OF PYX(?), IN PCE 2C THE FOLIATION
HAS AN ORTHOGONAL PATTERN BUT THEN BECOMES SUB-
HORIZONTAL MAINLY TO THE BASE OF THE CORE, MORE
STEEPLY INCLINED FOLIATION (60 DEGREES) IN PCE 2D AT
110CM AND IN PCE 2E, CALCITE VEIN TOP OF 2E AND
BOTTOM OF 2E HAS LIGHT GREY (N7) AND OLIVE (5Y4/4)
VEIN;
Comments : MEDIUM GREY (N5);
Vesicles : LARGE VESICLES OCCUR SPORADICALLY THROUGHOUT THE
SECTION ALWAYS LINED WITH A BLACK MINERAL, THE
CENTER IS EITHER AN INTERGROWTH OF BLACK (N2) AND
LIGHT GREY (N7) OR A MIXTURE OF LIGHT OLIVE GREY
(5Y6/2);
Groundmass : PLAGIOCLASE
PREDOMINANTLY PLAG LATHS;
PYROXENE
PYX(?) DISPOSED IN IRREGULAR PATCHES AS
FOLIATION;
Leg : 81 Top/Bottom Interval(mm): 0/ 380 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 617.88
Core: 51 Top of Core Depth (m) : 614.50
Sect: 3 Top of Section Depth(m): 617.50
LITHOLOGY: BASALT;
CONTINUED FROM 51-2;
Piece No. : PCES 1A (0-21), 1B (20-37);
Texture : PHYRIC;
Structure : PRINCIPAL VARIATION IS SHARP CHANGE IN ATTITUDE OF
FOLIATION FROM HORIZONTAL TO VERTICAL DOWNHOLE;
Comments : MEDIUM GREY (N5);
Vesicles : SPARSE VESICLES WITH LIGHT GREY (N7);
Leg : 81 Top/Bottom Interval(mm): 0/ 100 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 618.10
Core: 52 Top of Core Depth (m) : 618.00
Sect: 1 Top of Section Depth(m): 618.00
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (0-10);
Alteration : ALTERED;
Comments : BREAK BETWEEN 51-3 AND 52-1(?), DUSKY BLUE (5PB3/2)
LIGHT BROWNISH GREY (5YGR6/1), MEDIUM GREY (N5)
BASALT, BASE OF UNIT, SECTION PROBABLY MISSING(?);
Leg : 81 Top/Bottom Interval(mm): 100/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 619.50
Core: 52 Top of Core Depth (m) : 618.00
Sect: 1 Top of Section Depth(m): 618.10
LITHOLOGY: BASALT;
Piece No. : PCES 2A (10-52), 2B (51-82), 2C (80-104),
2D (103-124), 2E (124-128), 2F (128-145);
Texture : PHYRIC;
Structure : PRINCIPAL VARIATION DOWN CORE IS IN NUMBER AND
ABUNDANCE OF FOLIATION, IN PCE 2A FOLIATION IS
IRREGULAR BUT NEAR VERTICAL IN THE UPPER PART TO
CROSS CUT, A SEQUENCE OF INCLINED (50 DEGREES)
FOLIATION DECREASES IN INDURATION TO BECOME SUB-
HORIZONTAL AND ALSO THE SPACING DECREASES FROM
AROUND ABOVE TO 0.2CM IN THE LOWER PART, VEINS ARE
LINED WITH BLACK AND INFILLED IN THE LIGHT GREY (N7)
TO BLUISH WHITE (5B9/1) CRYSTALS (NOT FIBROUS)-
CALCITE(?), SLICKENSIDES ABSENT;
Comments : MEDIUM LIGHT GREY (N5);
Vesicles : SPARSE VESICLES PRESENT AND INFILLED WITH BLACK
(N2) OR BLACK INTERGROWN WITH LIGHT GREY (N7) AND
OCCASIONAL LIGHT OLIVE GREY (5Y6/1) PATCHES;
Groundmass : PLAGIOCLASE
PYROXENE
THESE DISPOSED IN FOLIATION OR IN SMALL IRREGULAR
PATCHES;
Leg : 81 Top/Bottom Interval(mm): 0/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 621.00
Core: 52 Top of Core Depth (m) : 618.00
Sect: 2 Top of Section Depth(m): 619.50
LITHOLOGY: BASALT;
CONTINUED FROM 52-1;
Piece No. : PCES 1A (1-50), 1B (50-75), 1C (73-78), 2 (80-83),
3 (85-90), 4 (91-95), 5 (97-100), 6 (102-105),
7 (107-110), 8 (111-118), 9 (120-123),
10 (125-134), 11 (136-137), 12 (140-143)
13 (145-149);
Texture : PHYRIC, MUCH FINER-GRAINED THAN 52-1;
Structure : PRINCIPAL VARIATION-WELL DEVELOPED FOLIATION IS
PRESENT AT THE TOP OF 1A (SPACING 3MM) BUT DECREASES
IN SPACING DOWN PCE TO 0.5CM BECOMING INCLINED, IN
THE SERIES OF SMALL PCES BELOW FOLIATION ENDS AT
70CM, SPARSE FOLIATION AT INTERVAL (68-85), IN PCE
10 BROKEN ALONG SLICKENSIDED FRACTURE (SLICKENSIDES
NEAR VERTICAL);
Comments : MEDIUM GREY (N5) BASALT, AT 140CM BASE OF FLOW AND
TOP OF FLOW BELOW;
Vesicles : Size(mm): 10 Percent:
LARGE 1CM OPEN VESICLES OFTEN APPEAR IN PCE 3
AND CONTINUE THROUGH PCE 5;
Size(mm): <2 Percent:
BELOW PCE 5 SMALL (2MM OR LESS) SIZE VESICLES
BECOME MORE ABUNDANT WITH AN ACCOMPANYING DECREASE
IN SIZE TO LESS THAN 1MM TOWARD THE BASE OF THE
FLOW, VESICLES RARE TO ABSENT IN PCES 1A-2,
VESICLES WITH BLACK LINING (N2) WITH TYPICAL LIGHT
GREY EUHEDRAL CRYSTALS IN OPEN ONES, LARGE
VESICLES AT INTERVAL (80-100), BELOW 100CM
INCREASING ABUNDANCE AND DECREASING SIZE OF SMALL
VESICLES;
Groundmass : PLAGIOCLASE
TYPICALLY FINE PLAG LATHS;
PYROXENE
Leg : 81 Top/Bottom Interval(mm): 0/ 300 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 621.30
Core: 52 Top of Core Depth (m) : 618.00
Sect: 3 Top of Section Depth(m): 621.00
LITHOLOGY: BASALTIC BRECCIA;
CONTINUED FROM 52-2;
Piece No. : PCES 1 (0-12), 2 (14-16), 3 (17-21), 4 (22-30);
Texture : PCE 1 HAS IRREGULAR BASALT CLASTS OF VESICULAR
BASALT SHOWING DIFFERENT DEGREES OF REDDENING AND
ARE SET IN A MATRIX OF SMALLER ANGULAR CLASTS,
SPARSE LARGE VESICLES PRESENT, IN PCE 2 ANGULAR
CLASTS OF REDDENED GREYISH RED (5R4/2), IN PCE 3
MEDIUM GREY (N5) VESICULAR (0.5CM) BASALT, IN PCE 4
CONTACT BETWEEN AGGLOMERATIC TOP OF FLOW AND
VESICULAR BASALT FLOW MEDIUM GREY (N5) VESICLES
(.5MM) PASSES UPWARD THROUGH REDDENED (5R4/2) ZONE
INTO AGGLOMERATE;
Leg : 81 Top/Bottom Interval(mm): 300/1360 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 622.36
Core: 52 Top of Core Depth (m) : 618.00
Sect: 3 Top of Section Depth(m): 621.30
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 5 (31-37), 6 (39-43), 7 (45-48), 8 (50-52),
9 (55-60), 10 (61-67), 11 (68-75), 12 (77-85),
13 (86-90), 14 (92-97), 15 (98-104), 16 (105-110),
17 (112-120), 18 (122-130), 19 (131-136);
Texture : PCE 7 HAS BRECCIATED BASALT AT BASE, CLASTS (0.3CM),
PCES 8-9 ARE BRECCIATED (AGGLOMERATE) GREYISH RED
BASALT (5R4/2);
Comments : PCES 5-7 ARE GREYISH RED (5R4/2) TO MEDIUM GREY, IN
PCES 8-9 CONTACT (GRADATIONAL) TO MEDIUM DARK GREY
(N5) VESICULAR BASALT, IN PCES 10-15 WEAK RED
(10R5/2), AT 130CM BASE OF FLOW, PCE 17 TOP OF FLOW;
Vesicles : IN PCES(3,5-7) VESICLES SHOW STRONG VERTICAL
ORIENTATION;
Size(mm): 3 Percent:
IN PCES 10-15, VESICLES TYPICALLY 3MM AND
FLATTENED WITH LARGE AXES VERTICAL, FLATTENING
DECREASES DOWNWARD, PCES 14-15 DO NOT SHOW
PREFERRED ORIENTATION AND HAVE ONLY ROUND TO SUB-
ROUNDED VESICLES, ABRUPT CHANGE TO SMALL VESICLES
BETWEEN PCES 15-16;
Size(mm): 0.1 Percent:
IN PCES 16+18 GREYISH RED (5R4/2) VESICLES(0.1MM)
TYPICAL, SPARSE LARGE 1CM VESICLES;
Size(mm): 10 Percent:
PCE 20, EXTREMELY VESICULAR;
Leg : 81 Top/Bottom Interval(mm): 1360/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 622.50
Core: 52 Top of Core Depth (m) : 618.00
Sect: 3 Top of Section Depth(m): 622.36
LITHOLOGY: BASALTIC BRECCIA;
Piece No. : PCE 20 (139-145);
Texture : PREDOMINANTLY MEDIUM DARK GREY (N4) TO GREYISH RED
PURPLE (5RP4/2) AGGLOMERATE, LARGE CLAST OF
VESICULAR BASALT WITH VESICLES OFTEN SHOWING STRONG
PREFERRED ORIENTATION;
Leg : 81 Top/Bottom Interval(mm): 0/ 450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 622.95
Core: 52 Top of Core Depth (m) : 618.00
Sect: 4 Top of Section Depth(m): 622.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 52-3;
Piece No. : PCES 1 (2-4), 2 (6-10), 3 (12-19), 4 (21-35),
5 (35-45);
Comments : VERY DUSKY RED PURPLE (5RP2/2) BASALT, PRINCIPAL
TREND TO TRANSITION AT 45CM IS DECREASE IN THE
PURPLE COLOR AND A CHANGE TO MEDIUM GREY (N5)
VESICULAR BASALT;
Vesicles : Size(mm): 0.5 Percent:
VESICLE SIZE UNIFORM THROUGHOUT WITH SPARSE OPEN
(1CM) VESICLES, SOME INDURATION OF PREFERRED
ORIENTATION OF VESICLES IN PCE 5;
Leg : 81 Top/Bottom Interval(mm): 450/ 980 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 623.48
Core: 52 Top of Core Depth (m) : 618.00
Sect: 4 Top of Section Depth(m): 622.95
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 6 (47-50), 7 (51-55), 8 (56-63), 9 (65-68),
10 (70-75), 11 (77-80), 12 (81-85), 13 (87-92),
14 (95-98);
Comments : MEDIUM LIGHT GREY (N6) BASALT;
Vesicles : Size(mm): 5 Percent:
LARGE IRREGULAR PARTLY OPEN AND INFILLED VESICLES
HAVE LONG AXES NEAR VERTICAL, VESICLES TYPICALLY
LINED WITH BLACK (N2), LIGHT GREY (N8) CORES
COMMON BUT OCCASIONAL BLUE GREEN (5BG7/2) PRESENT;
Leg : 81 Top/Bottom Interval(mm): 0/1480 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 624.98
Core: 53 Top of Core Depth (m) : 623.50
Sect: 1 Top of Section Depth(m): 623.50
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 52-4, THIN SECTION THOLEIITIC BASALT;
Piece No. : PCES 1 (1-4), 2 (6-10), 3 (13-16), 4 (21-24),
5 (27-32), 6A (35-42), 6B (43-65), 6C (65-80),
6D (80-95), 6E (94-107), 6F (105-125), 6G (125-136),
6H (136-148);
Texture : PHYRIC;
Structure : BLACK (N2) VEINS LINK STRING OF VESICLES, VARY IN
INCLINATION 40-60 DEGREES, PCE 6A IS CUT BY A
SLICKENSIDED FRACTURE INCLINED AT 60 DEGREES,
SLICKENSIDES ABSENT ACROSS THE FRACTURE PLANE AT 50
DEGREES, BELOW 65CM THE HORIZONTAL FOLIATION BECOMES
IMPORTANT, AT 107CM SLICKENSIDED FRACTURE;
Comments : MEDIUM GREY (N5) TO MEDIUM LIGHT GREY (N6);
Vesicles : Size(mm): 1-10 Percent:
Location: Filling: SMEC
PRINCIPAL VARIATION IS IN THE APPEARANCE OF STRING
OF VESICLES LINKED BY BLACK (N2) VEINS-THESE ARE
PREVALENT DOWN TO 65CM WITHIN THIS INTERVAL,
VESICLES RANGE IN SIZE FROM 1MM TO 1CM TYPICALLY
INFILLED BY BLACK (N2) SMEC, SOME PARTLY OPEN
VESICLES HAVE A LIGHT GREY (N7) CORE;
Location: Filling: QUARTZ, CALCITE
BELOW 65CM LARGE VESICLES ARE COMMON AND FORM
SMALL GEOIDS LINED WITH CALCITE AND QUARTZ BUT
OCCASIONALLY COMPLETELY INFILLED BY LIGHT BLUE
GREY (5B7/1) AND LIGHT GREENISH-GREY (5G8/1)
MINERALS;
Replacement: SMECTITE
CALCITE
QUARTZ
Leg : 81 Top/Bottom Interval(mm): 0/ 950 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 625.95
Core: 53 Top of Core Depth (m) : 623.50
Sect: 2 Top of Section Depth(m): 625.00
LITHOLOGY: VESICULAR BASALT;
CONTINUED FROM 53-1;
Piece No. : PCES 1A (1-20), 1B (14-38), 1C (39-50), 1D (48-63),
2 (64-89), 3 (90-94);
Texture : PHYRIC;
Structure : FOLIATION DIES OUT DOWNWARD AT 25CM, BETWEEN PCES
1A-1B FRACTURE WITH SLICKENSIDES;
Comments : MEDIUM GREY (N5) BASALT, TRANSITIONAL CONTACT AT
84CM, BASE OF FLOW AT 95CM, TOP OF NEW FLOW BELOW;
Vesicles : Size(mm): 2-10 Percent:
Location: Filling: SMEC
PRINCIPAL VARIATION IS A DOWNWARD INCREASE IN
VESICLE ABUNDANCE, VESICLES BECOME ESPECIALLY
ABUNDANT DOWN FROM 48CM, BETWEEN 48 AND 62CM
VESICLES AVERAGE 2-10MM IN DIAMETER, BELOW A SHARP
TRANSITION AT 62CM VESICLES DECREASE IN SIZE TO
BECOME SPARSE DOWNWARD;
Size(mm): 1-2 Percent:
Location: Filling: SMEC
BELOW A TRANSITIONAL CONTACT AT 84CM SMALL
VESICLES (1-2MM) AND SPARSE LARGE VESICLES BECOME
ABUNDANT TO THE BASE OF THE FLOW, VESICLES
TYPICALLY INFILLED WITH BLACK (N2) SMEC, LARGER
GREY (N7) AND YELLOWISH GREY (5Y6/1) PATCHES;
Groundmass : PLAGIOCLASE
PYROXENE
Replacement: SMECTITE
BLACK;
Leg : 81 Top/Bottom Interval(mm): 950/1450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 626.45
Core: 53 Top of Core Depth (m) : 623.50
Sect: 2 Top of Section Depth(m): 625.95
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 4 (95-101), 5 (103-108), 6 (110-112),
7 (114-117), 8 (118-120), 9 (122-124), 10 (126-128),
11 (130-133), 12 (135-138), 13 (140-143);
Comments : TOP OF FLOW AT 95CM, BLACKISH RED (5R2/2) TO DARK
GREY (N4) BASALT;
Vesicles : Size(mm): TO 10 Percent:
SMALL VESICLES IN UPPER PART GRADE DOWNWARD TO
LARGE (1CM) OPEN VESICLES IN LOWER (PCES 11-13)
ASSOCIATED WITH INCREASE IN GREY COLOR, VESICLES
LINED WITH BLACK AND INFILLED WHOLLY OR PARTLY
WITH LIGHT GREY (N7) OR MOD BLUE GREEN (5BG4/6);
Leg : 81 Top/Bottom Interval(mm): 0/ 340 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 626.84
Core: 53 Top of Core Depth (m) : 623.50
Sect: 3 Top of Section Depth(m): 626.50
LITHOLOGY: BASALTIC BRECCIA;
CONTINUED FROM 53-2;
Piece No. : PCES 1 (0-5), 2 (6-10), 3 (11-24), 4 (25-32);
Texture : MEDIUM DARK GREY (N4) BASALT BRECCIA, SMALL ANGULAR
BASALT FRAGMENTS (1MM) INTERBEDDED WITH VESICULAR
BASALT;
Comments : TOP OF SECTION IS BOUNDARY BETWEEN BASE OF ABOVE
UNIT AND THIS UNIT;
Vesicles : TOP OF UNIT (PCE 2) MUCH MORE VESICULAR;
Leg : 81 Top/Bottom Interval(mm): 340/ 580 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 627.08
Core: 53 Top of Core Depth (m) : 623.50
Sect: 3 Top of Section Depth(m): 626.84
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 5 (34-38), 6 (40-49), 7 (50-58);
Structure : DUSKY GREEN BAND AT 55CM;
Comments : BLACKISH RED (5R2/2) VESICULAR BASALT, PCE 7 IS
BLACKISH RED (5R2/2) TO DUSKY PURPLE (5RP2/2) TO
MEDIUM GREY (N5), IMPRESSION IS OF DOWNWARD DECREASE
IN REDDENING, GREEN COLOR ALSO DECREASES DOWNWARD
AND IS ABSENT IN MEDIUM GREY BASALT, BASE AND TOP OF
UNIT POSSIBLE AT 34CM;
Vesicles : VESICLES INFILLED LIGHT GREY AND DUSKY GREEN GREY
BUT LATTER COLOR IS BASALT;
Leg : 81 Top/Bottom Interval(mm): 590/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 628.00
Core: 53 Top of Core Depth (m) : 623.50
Sect: 3 Top of Section Depth(m): 627.09
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 8 (59-62), 9 (64-67), 10 (70-74), 11 (76-80),
12 (82-86), 13 (88-100), 14 (101-112), 15 (114-123),
16 (125-130), 17 (131-150);
Texture : PHYRIC;
Structure : INCIPIENT FOLIATION IS PRESENT, ONE NICE GEODE IS
PRESENT;
Comments : MEDIUM GREY (N5) VESICULAR BASALT, VESICLES ARE
ABUNDANT DOWN TO 101CM AND SHOW FOLDING INDICATING
LATE STAGE DEFORMATION OF FLOW;
Vesicles : VESICLES DECREASE BELOW 101CM AND BECOME SPARSE,
LARGE (2CM) VESICLES ARE DEVELOPED IN PCE 17,
VESICLES HAVE A LIGHT BLUISH GREY (5B7/1) OR
BLUISH WHITE (5B9/1) CORE, SOME HAVE A LIGHT BLUE
GREEN (5BG6/6) AND DUSKY BLUE GREEN (5BG3/2) CORE,
CONCENTRIC GROWTH IS EVIDENT AND ALL HAVE BLACK
LINING, LARGE VESICLE (3CM) LINED WITH BLACK WITH
LIGHT GREY (N7) AND YELLOWISH GREY (5Y8/1)
AMYGDALOIDAL CORE IN PCE 14;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
Leg : 81 Top/Bottom Interval(mm): 0/ 350 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 628.35
Core: 53 Top of Core Depth (m) : 623.50
Sect: 4 Top of Section Depth(m): 628.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 53-3;
Piece No. : PCES 1 (1-7), 2 (9-11), 3 (12-19), 4 (20-29),
5 (30-35);
Texture : PHYRIC, PATCHES (1-2MM) OF BLACK-WHITE INTERGROWN
CRYSTALS;
Comments : MEDIUM DARK GREY (N1), PCE 5 IS BASE OF UNIT AND
CONTACT WITH BRECCIATED TOP OF UNDERLYING FLOW WHICH
IS GREYISH RED (5R4/2) AND SHARP;
Vesicles : Size(mm): 1 Percent:
PREDOMINANTLY 1MM VESICLES IN SUB-HORIZONTAL
BANDS;
VESICULAR;
Leg : 81 Top/Bottom Interval(mm): 420/ 900 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 628.90
Core: 53 Top of Core Depth (m) : 623.50
Sect: 4 Top of Section Depth(m): 628.42
LITHOLOGY: PHYRIC BASALT;
Piece No. : PCE 7A (42-55), 7B (56-60), 7C (70-79), 8 (82-87);
Texture : PHYRIC, VESICLE CLASTS ARE PRESENT IN PCE 7B;
Structure : WEAK HORIZONTAL FOLIATION IS PRESENT, IN PCE 8 THERE
IS A 5MM VEIN LINED WITH BLACK (N2) SMECTITE AND
CENTRE IS PREDOMMINANTLY INTERGROWTH OF LIGHT BLUISH
GREY (5B7/1) AND BLUISH WHITE (5B9/1) WITH YELLOWISH
GREY PATCHES (5Y8/1) OCCURRING MORE SPARSELY;
Comments : MAIN BODY OF FLOW, MEDIUM GREY (N5);
Vesicles : VESICLES ARE SPARSE AND SOME VESICLE CLASTS ARE
PRESENT IN PCE 7B;
Leg : 81 Top/Bottom Interval(mm): 0/1400 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 633.90
Core: 54 Top of Core Depth (m) : 632.50
Sect: 1 Top of Section Depth(m): 632.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 1 (0-20), 2 (20-30), 3 (32-40), 4 (36-39),
5 (41-44), 6 (45-49), 7 (50-58), 8 (60-65),
9 (66-74), 10 (75-87), 11 (88-95), 12 (96-100),
13 (101-110), 14 (110-116), 15 (118-120),
16 (121-125), 17 (126-130), 18A (131-134),
18B (134-140);
Texture : PHYRIC, 3MM CLASTS OF BASALT ARE IN FAULT BRECCIA,
VESICLE CLASTS OCCUR IN PCE 7, PCE 10 HAS FRACTURE
WITH BASALT CLASTS;
Structure : SLICKENSIDED FRACTURE (63 DEGREES) IN PCE 1 WITH
SLICKENSIDES ORIENTED DOWNWARD ALONG FAULT PLANE,
BETWEEN (0-75CM) A WEAKLY DEVELOPED SUB-HORIZONTAL
FOLIATION IS PRESENT;
Comments : MEDIUM GREY (N5), AT 128CM A SHARP CONTACT DEFINES
THE BASE OF THE ABOVE;
Vesicles : VESICULAR, ONLY SPARSE LARGE VESICLES (0.5CM) ARE
PRESENT AND ARE BOTH OPEN AND INFILLED BETWEEN
(0-75CM), PCE 7 HAS VESICLE CLASTS (2CM), VESICLE
INFILL IS EITHER BLACK (N2) SMEC OR A MIX OF LIGHT
BLUISH GREY (5B7/1) AND YELLOWISH GREY (5Y8/1),
BELOW 75CM VESICLES INCREASE IN ABUNDANCE AND ARE
ARRANGED IN LAYERS OFTEN GRADED AND INCLINED AT 30
DEGREES, BELOW 110CM (PCE 14) VESICULATION IS IN
BANDS WITH LIGHT GREY (N6) ALMOST VESICLE FREE
BANDS (0.5CM) SEPARATING WIDE (3CM) BEDS
CONTINUING RANDOMLY DISTRIBUTED SMALL (1MM)
VESICLES, BELOW 128CM ABUNDANT VESICLES ARE
PRESENT;
Groundmass : PLAGIOCLASE
PYROXENE
AT 52CM EQUIGRANULAR PLAG LATHS AND PYX GRANULES,
105CM IS SIMILAR TO 52CM BUT INCLUDES
OCCASIONAL XENOLITHS OF PLAG AND PYX PHENOS, 135CM
IS APHYRIC(?) WITH VERY SMALL PLAG LATHS AND PYX;
Replacement: SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/ 380 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 634.38
Core: 54 Top of Core Depth (m) : 632.50
Sect: 2 Top of Section Depth(m): 634.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 54-1;
Piece No. : PCES 1 (0-13), 2 (14-17), 3 (20-21), 4 (24-28),
5 (30-32), 6 (33-37);
Texture : PHYRIC, PRINCIPAL VARIATION TOWARD BASE OF FLOW IS
DECREASE IN VESICLE SIZE AND GRAIN SIZE, PCE(6) HAS
CHILLED CONTACT;
Structure : BANDS ALTERNATING WITH SOME VESICLE FILLED AND
OTHERS FREE AND SOME INCLINED(30 DEGREES), SOME
SUGGESTION OF INVERTED GRADING;
Comments : MEDIUM GREY (N4), CONTACT WITH UNDERLYING FLOW
EVIDENT IN PCE(6)-BASE OF FLOW;
Vesicles : VESICLES IN PCE(1) FLATTENED AND CONCENTRATED IN
INCLINED BANDS (30 DEGREES) WITH INTERVENING
VESICLE FREE BANDS;
Groundmass : PLAGIOCLASE
SMALL PLAG LATHS;
PYROXENE
Leg : 81 Top/Bottom Interval(mm): 350/ 930 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 634.93
Core: 54 Top of Core Depth (m) : 632.50
Sect: 2 Top of Section Depth(m): 634.35
LITHOLOGY: AGGLOMERATE;
Piece No. : PCES 6 (34-37), 7 (39-42), 8 (43-49), 9 (52-57),
10 (59-69), 11 (70-80), 12 (82-87), 13 (89-92);
Texture : FRAGMENTS OF VESICULAR BASALT THAT ARE FREQUENTLY
ANGULAR AND RANGE IN SIZE FROM CM'S TO MM'S;
Comments : BOTTOM OF PCE 6 IS TOP OF FLOW AND PCE 13 IS BASE
OF AGGLOMERATE, BASALT IS BLACKISH RED (5R2/2) AND
VERY DUSKY RED(10R2/2) & VERY DUSKY PURPLE(5RP2/2);
Vesicles : SPARSE LARGE CM VESICLES GREYISH BLUE-GREEN
(5BG5/2) COMMON AND APPARENT BUT MINOR BELOW
PCE(11), VESICLES OFTEN VERTICAL ORIENTATION;
Leg : 81 Top/Bottom Interval(mm): 930/1460 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 635.46
Core: 54 Top of Core Depth (m) : 632.50
Sect: 2 Top of Section Depth(m): 634.93
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 14 (94-101), 15 (103-110), 16 (111-114),
17 (116-120), 18 (122-130), 19 (131-137),
20 (139-141), 21 (143-146);
Texture : A LARGE GREYISH BLACK (N2) CLAST (4CM) WITH REACTION
RIM PRESENT IN PCE(19);
Comments : MEDIUM DARK GREY (N4);
Vesicles : HIGHLY VESICULAR BASALT WITH ABUNDANT OFTEN
ELONGATE VESICLES (1-3MM) THROUGHOUT;
Leg : 81 Top/Bottom Interval(mm): 0/1390 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 636.89
Core: 54 Top of Core Depth (m) : 632.50
Sect: 3 Top of Section Depth(m): 635.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 54-2;
Piece No. : PCES 1 (0-5), 2 (7-10), 3 (12-16), 4 (18-21),
5 (23-26), 6 (27-33), 7 (35-53), 8A (54-65),
8B (65-76), 8C (76-93), 8D (91-118), 8E (117-139);
Texture : PHYRIC;
Structure : BETWEEN PCES(8C-8D) THERE IS A SLICKENSIDED FRACTURE
INCLINED 30 DEGREES, PRINCIPAL VARIATION IN PCE(8C)
IS APPEARANCE OF HORIZONTAL FOLIATION AND A WEAK
VERTICAL FOLIATION IN PCE(8C);
Comments : MED GREY (N5);
Vesicles : Size(mm): TO 1 Percent:
PCES(1,2) HAVE ABUNDANT SMALL VESICLES (1MM OR
LESS) WITH LARGER VESICLES RARE TO ABSENT;
Size(mm): 2-5 Percent:
PCES(3-7) HAVE IRREGULAR TO SUBROUNDED LARGE(2-
5MM) VESICLES ABUNDANT WITH VESICLE INFILL BLACK
(N2) AND DUSKY BLUE-GREEN (5BG3/2) AND BLUE-WHITE
(5B9/1) WITH MINOR YELLOWISH GREY (5Y8/1);
Size(mm): 1-5 Percent:
(10-50CM) SMALL VESICLES SPARSE, LARGE 1-5CM
VESICLES PRESENT, BLACK (N2) LINING INFILLED WITH
DUSKY BLUE-GREEN (5BG3/2) AND STRONG GEODAL
STRUCTURE, ONE LARGE VESICLE FILLED WITH LIGHT
BLUISH-GREY (5B7/2) WITH YELLOWISH GREY (5Y8/1),
VESICLES INCLINED 40 DEGREES, PCES 8C-8E HAS
SPARSE CONCENTRATION OF VESICLES, PCE(8E) HAS LARG
1.5CM VESICLE THAT IS INFILLED WITH YELLOWISH
GREY (5Y8/1) AND LIGHT GREY (N7);
Groundmass : PLAGIOCLASE
EQUIGRANULAR PLAG LATHS;
PYROXENE
CRYSTALS;
Leg : 81 Top/Bottom Interval(mm): 0/1450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 638.45
Core: 54 Top of Core Depth (m) : 632.50
Sect: 4 Top of Section Depth(m): 637.00
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 54-3;
Piece No. : PCES 1 (0-33), 2A (35-50), 2B (47-55), 2C (55-80),
2D (76-98), 2E (97-120), 2F (120-133), 2G (134-140),
2H (141-145);
Texture : PHYRIC, OCCASIONAL TRACHYTE TEXTURE OBSERVED IN
GROUNDMASS;
Structure : PRINCIPAL VARIATION IS IN DEGREE OF DEVELOPMENT OF
THE WEAK FOLIATION, A NICE CONTACT BETWEEN NEAR
VERTICAL FRACTURES AND SUB-HORIZONTAL BRAIDED
FOLIATION CLEAR IN PCE 2E, SLICKENSIDED FRACTURE
(40 DEGREES) WITH FIBROUS CALCITE;
Comments : MED GREY (N5), A NICE CONTACT CLEAR IN PCE(2E);
Vesicles : VESICLES ARE RARE TO ABSENT THROUGHOUT;
Groundmass : PYROXENE
PLAGIOCLASE
PLAG LATHS AND PYX IN NEARLY EQUAL PROPORTIONS
SHOWING OCCASIONAL TRACHYTE TEXTURE;
Replacement: CALCITE
FIBROUS;
Leg : 81 Top/Bottom Interval(mm): 0/1100 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 639.60
Core: 54 Top of Core Depth (m) : 632.50
Sect: 5 Top of Section Depth(m): 638.50
LITHOLOGY: PHYRIC BASALT;
Piece No. : PCES 1A (0-13), 1B (13-24), 1C (24-38), 2 (40-48),
3 (50-60), 4 (61-75), 5 (76-87), 6 (89-102),
7 (103-110);
Texture : PHYRIC;
Structure : AT 130CM THERE IS A SLICKENSIDED FRACTURE(INCLINED
60 DEGREES) WITH SLICKENSIDES PARALLEL TO VERTICAL
AXIS, 29CM HAS A 70 DEGREE INCLINED SLICKENSIDED
FRACTURE WITH SLICKENSIDES INCLINED AT 50 DEGREES TO
HORIZONTAL, PCE(2)-FACE OF FRACTURE IN THESE PCES,
PRINCIPAL FEATURE IS THE WELL-DEVELOPED BRAIDED
FOLIATION ALSO SEEN IN THE LOWER PART OF 54-4;
Comments : MED GREY (N5);
Groundmass : PYROXENE
PLAGIOCLASE
PLAG LATHS PREDOMINATE WITH SUBORDINATE PYX;
Leg : 81 Top/Bottom Interval(mm): 0/ 330 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 641.83
Core: 55 Top of Core Depth (m) : 641.50
Sect: 1 Top of Section Depth(m): 641.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (1-6), 2 (7-10), 3 (12-20), 4 (23-28),
5 (30-33);
Texture : PCE(2) CONTAINS AN ANGULAR CLAST OF GREYISH RED
BASALT, COULD BE AN AGGLOMERATE(?);
Comments : PCE(1) IS TOP OF UNIT AND CONTINUED FROM 54-5,
GREYISH RED (5R4/2), A VERY DUSKY RED(10R2/2) MATRIX
A SIMILAR LITHOLOGY IS IN PCE(6);
Vesicles : VESICULAR BASALT;
Leg : 81 Top/Bottom Interval(mm): 350/ 560 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 642.06
Core: 55 Top of Core Depth (m) : 641.50
Sect: 1 Top of Section Depth(m): 641.85
LITHOLOGY: AGGLOMERATE;
Piece No. : PCES 6 (35-40), 7 (41-51), 8 (53-56);
Texture : AGGLOMERATE, CLASTS ARE VESICULAR BASALT REDDENED AT
EDGES, EDGES OF CLASTS HAVE WELDED ASPECT(?);
Structure : INTERSTICES AMYGDALOIDAL;
Comments : VERY DUSKY RED(10R2/2) TO GREYISH RED PURPLE(5RP4/2)
CLASTS;
Vesicles : INTERSTICES AMYGDALOIDAL AND INFILLED WITH
GREYISH-BLUE GREEN(5BG5/2) TO MOD BLUE-GREEN
(5BG4/6) MINERAL;
Leg : 81 Top/Bottom Interval(mm): 590/1150 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 642.65
Core: 55 Top of Core Depth (m) : 641.50
Sect: 1 Top of Section Depth(m): 642.09
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 9 (59-62), 10 (65-71), 11 (73-77), 12 (80-83),
13 (85-91), 14 (92-96), 15 (99-105), 16 (107-110),
17 (112-115);
Texture : THIN AMYGDULAR CORE AT LIGHT GREENISH GREY(5G8/1)
EUHEDRA;
Comments : VESICULAR VERY DUSKY RED(10R2/2) TO GREYISH RED
PURPLE(5RP4/2) BASALT;
Vesicles : Size(mm): 1-2 Percent:
VESICLE SIZES 1-2MM BUT OCCASIONAL MAJOR
VESICLES(3-4CM) PRESENT, VESICLES INFILLED WITH
OUTER BLACK(N2) LINING THEN MOD BLUE-GREEN(5BG4/6)
LAYER, THIN AMYGDULAR CORE AT LIGHT GREENISH GREY
(5G8/1) EUHEDRA;
Leg : 81 Top/Bottom Interval(mm): 1160/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 643.00
Core: 55 Top of Core Depth (m) : 641.50
Sect: 1 Top of Section Depth(m): 642.66
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 18 (116-120), 19 (122-125), 20 (127-131),
21 (133-150);
Texture : PHYRIC, CHARACTERIZED BY 1-2CM VESICLE CLASTS;
Comments : MED GREY(N5);
Vesicles : VESICULAR BASALT CHARACTERIZED BY 1-2CM VESICLE
CLASTS, VESICLES SHOW SOME COLOR PATTERN AS ABOVE;
Groundmass : PYROXENE
PLAGIOCLASE
PLAG LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/1200 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 644.20
Core: 55 Top of Core Depth (m) : 641.50
Sect: 2 Top of Section Depth(m): 643.00
LITHOLOGY: AGGLOMERATE;
Piece No. : PCES 1 (1-6), 2 (9-12), 3 (14-17), 4 (20-24),
5 (26-36), 6 (39-46), 7 (59-65), 8 (67-80),
9 (82-88), 10 (90-97), 11 (99-103), 12 (105-113);
Texture : AGGLOMERATE, CLASTS OF BASALT (3-5CM) IN MATRIX OF
SMALLER ANGULAR CLASTS (3MM OR LESS) OF SAME, PCE 12
IS GRADATIONAL BASE OF AGGLOMERATE;
Structure : SCORIACEOUS TOP(?);
Comments : PCE (1) IS TOP OF UNIT (?), DUSKY BLUE (5PB3/2), RED
DUSKY PURPLE (5RP2/2) AND GREYISH RED PURPLE (5RP4/2
CLASTS OF BASALT, MATRIX OF SMALLER CLASTS OF
BASALT, REDDENING (5R4/2) APPARENT AROUND BASALT
CLASTS, PCE(12) IS GARADATIONAL BASE OF AGGLOMERATE;
Vesicles : LARGE IRREGULAR VESICLES REPRESENT INFILLED
INTERSTICES IN CLASTS, VESICLES TYPICALLY
INFILLED WITH OLIVE (5Y5/4);
Leg : 81 Top/Bottom Interval(mm): 1200/1450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 644.45
Core: 55 Top of Core Depth (m) : 641.50
Sect: 2 Top of Section Depth(m): 644.20
LITHOLOGY: PHYRIC BASALT;
Piece No. : PCES 13A (121-135), 13B (135-145);
Texture : PHYRIC, BECOMES BRECCIATED AGAIN TOWARDS THE BASE;
Structure : VERTICAL TO INCLINED JOINTS PRESENT AND INFILLED
WITH BLACK (N2) OR OLIVE (5Y5/4) MINERAL;
Comments : MEDIUM DARK GREY (N4);
Leg : 81 Top/Bottom Interval(mm): 0/1100 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 645.60
Core: 55 Top of Core Depth (m) : 641.50
Sect: 3 Top of Section Depth(m): 644.50
LITHOLOGY: SCORIA/AGGLOMERATE;
CONTINUED FROM 55-2;
Piece No. : PCES 1 (1-10), 2 (12-20), 3A (21-28), 3B (29-35),
3C (35-41), 3D (41-48), 4 (50-58), 5A (60-65),
5B (65-70), 5C (70-80), 5D (80-85), 5E (85-90),
6 (92-103), 7 (104-111);
Texture : VESICULAR CLASTS OF BASALT WITH CLASTS ROUNDED TO
SUBROUNDED, LARGE CLASTS UP TO 3CM IN DIAMETER WITH
AN ABUNDANCE OF SMALLER 5MM CLASTS IN A MATRIX OF
SMALLER CLASTS OF THE SAME;
Structure : CLASTS SHOW FRACTURING, SCORIA/AGGLOMERATE;
Alteration : CLASTS SHOW CORROSION;
Comments : MATRIX OF SMALLER BASALT CLASTS, DUSKY BLUE (5PB3/2)
AND VERY DUSKY PURPLE (5RP2/2) AND GREYISH RED PURPL
(5RP4/2) VESICULAR CLASTS, DUSKY BLUE GREEN MINERAL
COMMON IN INTERSTICES AND VESICLES AND VEINING
CLASTS, PCE(7) IS BASE OF SCORIA/AGGLOMERATE;
Vesicles : VESICLES PRESENT THROUGHOUT WHICH HAVE FORMED IN
THE INTERSTICES, VESICULAR CLASTS;
Leg : 81 Top/Bottom Interval(mm): 1100/1380 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 645.88
Core: 55 Top of Core Depth (m) : 641.50
Sect: 3 Top of Section Depth(m): 645.60
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCE 8 (111-137);
Texture : PHYRIC, CLASTS WITH REACTION RIMS IN THE UPPER PART
OF PCE (8);
Comments : MED GREY (N5);
Vesicles : Size(mm): 0.5 Percent:
ABUNDANT SMALL VESICLES (0.5MM) WITH SEVERAL 1CM
SIZE VESICLE CLASTS;
Leg : 81 Top/Bottom Interval(mm): 0/1440 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 647.44
Core: 55 Top of Core Depth (m) : 641.50
Sect: 4 Top of Section Depth(m): 646.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 1A (0-45), 1B (45-65), 2A (67-81), 2B (81-90),
3 (91-144);
Texture : PHYRIC, SOME TRACHYTIC TEXTURE DEVELOPED BETWEEN
100-110CM AND AROUND CLASTS BETWEEN 0-10CM;
Structure : PRINCIPAL VARIATION IS IN THE DISTRIBUTION OF
VESICLES AND VEINED MICROFRACTURES, BELOW BETWEEN
(33-70CM) ABUNDANT ANASTOMOSING VEIN FILLED FRACTURE
INCLINED AT 30-50 DEGREES, FAINT VERTICAL FOLIATION
IS PRESENT TOWARDS THE BASE OF PCE (3), SLICKENSIDED
FRACTURE INCLINED AT 40 DEGREES;
Comments : MED GREY (N5), AT 5CM VESICLES EXHIBIT FLOW
CIRCULATION AROUND LARGE CLAST AND AGAIN AT 20CM;
Vesicles : BELOW 5CM VESICLES EXHIBIT FLOW CIRCULATION,
VESICLES ALSO DISPOSED IN AN INCLINE(40 DEGREES)
AT 32CM, A PREFERRED INCLINATION OF THE VESICLES
ALSO AT 86CM(INCLINED 40 DEGREES), A LARGE ZONE OF
MORE VESICULAR BASALT BETWEEN 98 & 110CM IS
BOUNDED BY PHYRIC BASALT IN WHICH VESICLES ARE
MINOR;
Groundmass : PYROXENE
PLAGIOCLASE
PLAG LATHS AND PYX (ALTERED ?) WITH SOME TRACHYTE
TEXTURE DEVELOPED BETWEEN 100-110CM AND AROUND
CLASTS BETWEEN 0-10CM;
Leg : 81 Top/Bottom Interval(mm): 0/1170 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 648.67
Core: 55 Top of Core Depth (m) : 641.50
Sect: 5 Top of Section Depth(m): 647.50
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 55-4;
Piece No. : PCES 1A (0-13), 1B (14-24), 1C (25-37), 1D (37-52),
1E (52-59), 1F (57-74), 1G (74-94), 1H (94-117);
Texture : PHYRIC;
Structure : VARIATION DOWN SECTION IN THE DEVELOPMENT OF VEIN
FRACTURE FILLING, 6-67CM NO FOLIATION, 67CM THERE IS
A ZONE OF VERTICAL FRACTURE VEIN FILLING, 75-94CM
INCLINED FOLIATION AND VEINS LINKING SPARSE VESICLES
(INCLINED 30 DEGREES), BELOW 100CM PROMINENT VEIN
(SPACING 0.5CM-THICKNESS 1MM) INCLINED AT 45 DEGREES
AND SEPARATED BY 3CM BAND OF UNFRACTURED UNVEINED
PHYRIC BASALT, 111CM HAS ANASTOMOSING PATTERN OF
VEINS FRACTURING;
Alteration : GROUNDMASS PLAG AND PYX ALTERED;
Comments : MED GREY, 67CM HAS SHARP CONTACT BETWEEN UNFRACTURED
BASALT AND ZONE OF VERTICAL FRACTURE VEIN FILLING;
Vesicles : SPARSE VESICLES AT 75-94CM ARE LINKED BY INCLINED
FOLIATION AND VEINS, PRINCIPAL VARIATION DOWN
SECTION IS IN THE ABUNDANCE OF MINOR CONCENTRATION
OF VESICLES, 0-6CM VERTICAL TRAINS OF VESICLES,
6-67CM VESICLES RARE AND SPARSE VESICLE CLASTS;
Groundmass : PYROXENE
PLAGIOCLASE
ALTERED PLAG LATHS AND PYX GRAINS;
Leg : 81 Top/Bottom Interval(mm): 0/1060 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 650.06
Core: 55 Top of Core Depth (m) : 641.50
Sect: 6 Top of Section Depth(m): 649.00
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 55-5;
Piece No. : PCES 1A (0-44), 1B (44-53), 1C (53-66), 1D (66-88),
1E (89-106);
Texture : PHYRIC, PCE(1A) HAS A LARGE VESICULAR CLAST SHOWING
WELL-DEVELOPED GRADING, SPARSE VESICLE CLASTS,
FOLIATION OFTEN SHOWS FLOW TEXTURE;
Structure : PRINCIPAL VARIATION IN THE SECTION IS IN THE
APPEARANCE OF A WELL-DEVELOPED FOLIATION OFTEN
SHOWING FLOW TEXTURE AND FREQUENTLY FOLLOWED BY
FLATTENED VESICLES;
Comments : MED GREY (N5);
Vesicles : VESICLES INCREASE IN ABUNDANCE TO SPARSE TOWARDS
BASE AND ARE FILLED WITH BLACK (N2) OR DUSKY BLUE
GREEN (5BG3/2) INSIDE BLACK LINING, OCCASIONAL
LIGHT BLUISH GREY INFILL WITH YELLOWISH GREY
(5Y8/1) PATCHES INTERGROWN WITH BLACK (N2) BOTH
LINING AND WITHIN VESICLE CENTER;
Groundmass : PYROXENE
PLAGIOCLASE
PLAG LATHS AND PYX THAT HAVE ALTERED TO BROWN(?);
Leg : 81 Top/Bottom Interval(mm): 0/ 700 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 651.20
Core: 56 Top of Core Depth (m) : 650.50
Sect: 1 Top of Section Depth(m): 650.50
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 55-6;
Piece No. : PCES 1 (2-8), 2 (10-20), 3 (23-27), 4 (30-34),
5 (35-39), 6 (41-44), 7 (46-63), 8 (66-69);
Texture : PHYRIC, SMALL 1CM VESICLE CLASTS IN PCE(1),
BRECCIATION OF BASALT;
Structure : WEAK FOLIATION IS PRESENT, VEINING ASSOCIATED WITH
BRECCIATION OF THE BASALT EXTENDS THROUGH PCES(2-5);
PCE(7) HAS VEIN INCLINED AT 80 DEGREES WITH
SLICKENSIDES AT 70 DEGREES TO CUT PIECE OF CORE;
Comments : MED GREY (N5), SHARP TRANSITION IN VESICLE ABUNDANCE
AT 49CM, PCE(8) IS BASE OF FLOW, CONTACT BETWEEN
PCES(8-9) APPEARS CHILLED;
Vesicles : PRINCIPAL LITHOLOGIC VARIATION IN TOP 49CM IS A
GRADUAL INCREASE IN NUMBER OF VESICLES, THE SPARSE
VESICLES ARE GENERALLY 0.5CM IN SIZE AND TYPICALLY
FLATTENED, SMALL 1CM VESICLE CLASTS IN PCE(1),
SHARP TRANSITION FROM SPARSE LARGE VESICLES TO
ABUNDANT VESICLES OF UNIFORM 1MM SIZE, TOWARDS
BASE OF PCE(7) VESICLES DECREASE IN SIZE TO 0.1MM;
Leg : 81 Top/Bottom Interval(mm): 700/ 870 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 651.37
Core: 56 Top of Core Depth (m) : 650.50
Sect: 1 Top of Section Depth(m): 651.20
LITHOLOGY: APHYRIC BASALT;
SCORIACEOUS AGGLOMERATE;
Piece No. : PCES 9 (70-75), 10 (76-87);
Texture : APHYRIC, CONTACT BETWEEN PCES(8-9) APPEAR CHILLED,
ANGULAR CORRODED AND FRACTURED CLASTS(SIZES 1-2MM);
Structure : FRACTURED CLASTS, SCORIACEOUS;
Comments : CONTACT IN PCES(8-9), PCE(9) IS TOP OF FLOW, VERY
DUSKY PURPLE (5RP2/2) AND GREYISH PURPLE (5RP4/2) AN
MEDIUM GREY (N5) BASALT, MATRIX BETWEEN ANGULAR
CORRODED AND FRACTURED CLASTS IS VERY DARK RED
(5R2/6), SCORIACEOUS AGGLOMERATE;
Vesicles : SPARSE VESICLES DEVELOPED IN INTERSTICES ARE
INFILLED WITH PALE OLIVE (5Y6/1) INTERGROWN WITH
BLACK (N2) AND LIGHT BLUISH GREY (5B7/1) CRYSTALS;
Leg : 81 Top/Bottom Interval(mm): 900/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 652.00
Core: 56 Top of Core Depth (m) : 650.50
Sect: 1 Top of Section Depth(m): 651.40
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 11 (90-95), 12 (98-102), 13 (104-110),
14 (113-116), 15 (119-126), 16 (134-138),
17 (142-144), 18 (146-150);
Texture : PHYRIC, APHYRIC TO APHANITIC GROUNDMASS;
Comments : GREYISH RED PURPLE(5RP4/2) DIMINISHES DOWNWARDS
THROUGH DUSKY BLUE(5PB3/2) TO MEDIUM GREY(N5)
BASALT, MINOR REDDENING PRESENT IN PCE(16);
Vesicles : VESICULAR THROUGHOUT WITH VESICLES ENTRAINED
EITHER HORIZONTALLY (PCE 15B) OR VERTICALLY(PCE
15A);
Groundmass : APHYRIC TO APHANITIC BUT NOT RESOLVABLE WITH
BINOCULAR SCOPE;
Leg : 81 Top/Bottom Interval(mm): 0/1460 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 653.46
Core: 56 Top of Core Depth (m) : 650.50
Sect: 2 Top of Section Depth(m): 652.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 56-1;
Piece No. : PCES 1 (2-5), 2 (7-10), 3 (13-15), 4 (18-26),
5 (27-41), 6 (42-50), 7 (52-57), 8 (60-72),
9 (74-77), 10 (80-88), 11 (91-96), 12 (98-101),
13 (105-108), 14 (110-114), 15 (117-121),
16 (125-128), 17 (130-135), 18 (142-146);
Texture : PHYRIC, TRACHYTIC TEXTURE EXHIBITED IN GROUNDMASS;
Structure : NO VEINING OR FAULTING IS PRESENT;
Vesicles : PRINCIPAL VARIATION IS AN INCREASE IN VESICLE SIZE
IN PCES(1,2) TO REACH A UNIFORM 3MM SIZE THAT
CONTINUES DOWN TO THE BASE OF THE SECTION,
VESICLES ARE TYPICALLY INFILLED WITH BLACK (N2)
SMEC BUT LIGHT BLUISH GREY(5B7/1) AND GREYISH BLUE
GREEN(5BGB/2) INFILLS ARE ALSO PRESENT;
Groundmass : PYROXENE
PLAGIOCLASE
PREDOMINANTLY PLAG LATHS AND PYX CRYSTALS SHOWING
TRACHYTIC TEXTURE;
Replacement: SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/ 980 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 654.48
Core: 56 Top of Core Depth (m) : 650.50
Sect: 3 Top of Section Depth(m): 653.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 56-2;
Piece No. : PCES 1 (1-10), 2A (14-20), 2B (20-27), 2C (29-40),
2D (40-47), 3 (50-55), 4 (57-59), 5 (61-64),
6 (66-68), 7 (72-74), 8 (76-81), 9 (84-88),
10 (91-98);
Texture : PHYRIC;
Structure : FRACTURE INCLINED(60 DEGREES) AND SLICKENSIDES BUT
NO DISPLACEMENT VISIBLE IN CROSSCUT VESICLES;
Vesicles : ABUNDANT 3MM VESICLES OCCUR DOWN TO 50CM BUT THEN
DECREASE IN NUMBER TO 90CM, PCE(10) SHOWS A SHARP
INCREASE IN VESICLE ABUNDANCE WITH AN ASSOCIATED
DECREASE IN SIZE TO 1MM, THIS IS PROBABLY THE
VESICULATED ZONE AT THE BASE OF THE FLOW,
VESICLES ARE PREDOMINANTLY INFILLED WITH BLACK (N2
SMECTITE, SOME HAVE LIGHT BLUISH GREY (5B7/1) AND
BLACK (N2) INTERGROWTH WITH SPARSE LIGHT OLIVE GRE
(5Y6/1) INTERGROWTH;
Leg : 81 Top/Bottom Interval(mm): 1000/1320 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 654.82
Core: 56 Top of Core Depth (m) : 650.50
Sect: 3 Top of Section Depth(m): 654.50
LITHOLOGY: BRECCIATED VESICULAR BASALT;
Piece No. : PCES 11 (100-107), 12 (111-125), 13 (128-132);
Texture : PCES OF BRECCIATED VESICULAR BASALT;
Structure : VESICLE AND FRACTURE VEIN FILLING IN BRECCIA;
Comments : PCE(11) IS BASE AND TOP OF FLOW CA 100CM, NOMINAL
ONLY-SMALL PIECES IN THIS SECTION AND TOP OF 57-1
SUGGEST NOT IN PLACE TO WITHIN 3M OR SO, MEDIUM
GREY (N5) TO GREYISH RED (5R4/2), VESICLES AND
FRACTURE VEIN FILLING IN BRECCIA IS PALE BLUE-GREEN
(5BG7/2) COLOR;
Vesicles : VESICULAR;
Leg : 81 Top/Bottom Interval(mm): 0/ 530 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 660.03
Core: 57 Top of Core Depth (m) : 659.50
Sect: 1 Top of Section Depth(m): 659.50
LITHOLOGY: PHYRIC VESICULAR BASALT AND SCORIACEOUS BASALT;
CONTINUED FROM 56-3;
Piece No. : PCES 1 (1-8), 2 (11-13), 3 (18-23), 4 (26-28),
5 (32-34), 6 (37-39), 7 (41-53);
Texture : MIXTURE OF PHYRIC VESICULAR AND SCORIACEOUS BASALT;
Structure : SCORIACEOUS BASALT;
Comments : THE PCES ARE NOT IN PLACE, THE MEDIUM GREY BASALT
PROBABLY DERIVES FROM THE OVERLYING FLOW AND THE
HIGHLY VESICULAR PCES(1-3,5) PROBABLY REPRESENT ITS
BASE, THE REMAINING SCORIACEOUS BASALT PCES(4,7)
PROBABLY REPRESENT THE TOP OF THE UNDERLYING FLOW;
Vesicles : SMALL VESICLE SIZE AND HIGHLY VESICULAR PCES(1-3,
& 5);
Leg : 81 Top/Bottom Interval(mm): 550/ 650 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 660.15
Core: 57 Top of Core Depth (m) : 659.50
Sect: 1 Top of Section Depth(m): 660.05
LITHOLOGY: SCORIACEOUS/AGGLOMERATE;
Piece No. : PCE 8 (55-65);
Texture : SCORIACEOUS/AGGLOMERATE, ANGULAR BASALTIC CLASTS;
Structure : SCORIACEOUS;
Comments : GREYISH RED (5R4/2) TO DUSKY RED (5R3/4) CLASTS SET
IN BLACKISH RED MATRIX (5R2/2);
Vesicles : VESICULAR INTERSTICES PART INFILLED WITH OLIVE
(5Y5/6);
Leg : 81 Top/Bottom Interval(mm): 650/1500 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 661.00
Core: 57 Top of Core Depth (m) : 659.50
Sect: 1 Top of Section Depth(m): 660.15
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 9 (65-74), 10 (75-79), 11 (81-84),
12 (86-89), 13 (91-94), 14 (96-99), 15 (101-104),
16 (106-116), 17 (118-123), 18 (125-130),
19 (132-150);
Texture : PCES 16-18 ARE MORE COARSELY VESICULAR WITH SPARSE
GLOMEROPHYRIC PATCHES OF PLAG AND PYX PHENOS IN
GROUNDMASS;
Comments : PCES(9-18) ARE MEDIUM GREY VESICULAR BASALT;
Vesicles : Size(mm): 1-3 Percent:
PCES(9-12) VESICLES SHOW GAS STREAMING AND ARE
TYPICALLY 1-3MM IN SIZE WITH LIGHT OLIVE GREY
(5Y6/1) CENTRES;
Size(mm): <1 Percent:
PCES (13-15) VESICLES ARE MUCH SMALLER;
Size(mm): 5-10 Percent:
PCES(16-18) HAVE LARGE OPEN VESICLES PARTLY
INFILLED WITH LIGHT OLIVE GREY (5Y6/1);
Groundmass : PYROXENE
ALTERED(REDDENED);
PLAGIOCLASE
PLAG LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/ 440 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 661.44
Core: 57 Top of Core Depth (m) : 659.50
Sect: 2 Top of Section Depth(m): 661.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 57-1;
Piece No. : PCES 1 (0-22), 2 (24-36), 3 (38-44);
Texture : PCE(1) CONSISTS OF FOUR PEBBLES OF PHYRIC VESICULAR
BASALT AND ONE PEBBLE OF SCORIACEOUS LAVA(SEE 57-2),
PCES(2,3) ARE PHYRIC VESICULAR BASALT;
Comments : MED GREY (N5) BASALT, PEBBLES IN PCE(1) NOT IN PLACE
FOR PEBBLE OF SCORIACEOUS LAVA SEE 57-2;
Vesicles : PCES(2,3) SHOW SOME SEGREGATION OF VESICLE SIZE;
Leg : 81 Top/Bottom Interval(mm): 0/ 210 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 668.71
Core: 58 Top of Core Depth (m) : 668.50
Sect: 1 Top of Section Depth(m): 668.50
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 1 (1-5), 2 (8-16), 3 (18-21);
Texture : PLAG PHENOS (LATHS) COMMON AND GLOMEROPHYRES OF PLAG
AND PYX;
Comments : PCE 1 IS TOP OF FLOW, GREYISH RED (5R4/2) BASALT;
Vesicles : VESICULAR BASALT, VESICLES LINED WITH GREYISH BLUE
GREEN (5BG5/2);
Groundmass : PYROXENE
ALTERED;
PLAGIOCLASE
FINE PLAG LATHS;
Leg : 81 Top/Bottom Interval(mm): 230/1450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 669.95
Core: 58 Top of Core Depth (m) : 668.50
Sect: 1 Top of Section Depth(m): 668.73
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 4A (23-33), 4B (32-47), 4C (46-54), 4D (54-80),
4E (79-92), 5 (94-97), 6A (100-105), 6B (105-110),
6C (109-113), 7A (115-124), 7B (124-128),
8A (130-140), 8B (140-145);
Texture : PHYRIC, ZONES OF HIGH VESICLE CONCENTRATION SHOW
BOTH GRADING AND INVERTED GRADING, THESE ZONES ARE
SEPARATED BY VESICLE FREE ZONES OF FINE-GRAIN SIZE,
ZONATION IN THE VESICLE RICH/POOR ZONES IS GENERALLY
SUB-HORIZONTAL TO INCLINED (10 DEGREES) BUT AN
INCLINED ZONE (50 DEGREES) IS PRESENT IN PCE(6E),
SPARSE PHENOS ARE GLOMEROPHYRIC;
Structure : VESICLE FREE ZONES HAVE VEINS COMPOSED OF BLACK (N2)
SMEC WHICH HAVE A DISTINCT EN-ECHELON APPEARANCE
FOLLOWING THE LINE OF CONTACT BETWEEN THE VESICLE
RICH AND VESICLE POOR ZONES-THE PATTERN IS
REMINISCENT OF RIEDEL SHEARING;
Comments : MED GREY (N5), VESICLE FREE AREA FINER IN GRAIN BUT
WITH SAME MINERAL COMPOSITION, RIEDEL FRACTURES HAVE
SAME COLOR COMPOSITION AND BANDING AS VESICLES;
Vesicles : Size(mm): 1-3 Percent:
THE PRINCIPAL CHARACTERISTIC IN THE VARIATION IN
ABUNDANCE OF VESICLES IS THEIR CONCENTRATION IN
DISCRETE ZONES, ZONES OF HIGH VESICLE
CONCENTRATION SHOW BOTH GRADING AND INVERTED
GRADING WHICH ARE SEPARATED BY VESICLE FREE ZONES,
VESICLES TYPICALLY LINED WITH BLACK (N2) THEN DUSK
BLUE GREEN (5BG3/2) THEN BROWNISH GREY (5YR4/1)
CORE;
Groundmass : PYROXENE
PLAGIOCLASE
COARSER PLAG LATHS IN VESICULAR BASALTS;
Replacement: SMECTITE
Leg : 81 Top/Bottom Interval(mm): 0/ 270 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 670.27
Core: 58 Top of Core Depth (m) : 668.50
Sect: 2 Top of Section Depth(m): 670.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 58-1;
Piece No. : PCES 1A (1-8), 1B (8-15), 2 (18-20), 3 (22-27);
Texture : PHYRIC;
Structure : TRACES OF SLICKENSIDES ON FRACTURE (INCLINED);
Comments : MED GREY (N5), DARK GREENISH YELLOW DEVELOPED ALONG
FRACTURE FACE;
Vesicles : Size(mm): 1 Percent:
VESICLES ARE CONCENTRATED IN HORIZONTAL BEDS WITH
VESICLE FREE MATERIAL BETWEEN;
Leg : 81 Top/Bottom Interval(mm): 300/ 410 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 670.41
Core: 58 Top of Core Depth (m) : 668.50
Sect: 2 Top of Section Depth(m): 670.30
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 4 (30-34), 5 (37-41);
Texture : THICK, FINER-GRAINED;
Comments : DARK GREY SHOWING SOME REDDENING, 30CM IS TOP OF
FLOW UNIT;
Vesicles : VESICULAR;
Groundmass : PYROXENE
PLAGIOCLASE
LATHS;
Leg : 81 Top/Bottom Interval(mm): 500/ 610 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 670.61
Core: 58 Top of Core Depth (m) : 668.50
Sect: 2 Top of Section Depth(m): 670.50
LITHOLOGY: SCORIACEOUS VESICULAR BASALT;
Piece No. : PCES 7 (50-55), 8 (57-61);
Structure : SCORIACEOUS;
Comments : DUSKY RED (5R3/4);
Vesicles : VESICULAR, GREYISH GREEN (5G5/2) INFILL TO
VESICLES;
Leg : 81 Top/Bottom Interval(mm): 620/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 671.47
Core: 58 Top of Core Depth (m) : 668.50
Sect: 2 Top of Section Depth(m): 670.62
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 9A (62-75), 9B (76-87), 10 (87-96),
11A (105-117), 11B (117-139), 12 (140-147);
Texture : PHYRIC, SUGGESTION OF A DECREASE IN GRAIN-SIZE
ACROSS VESICLE RICH/POOR TRANSITION;
Structure : DISTINCT GRADING ALSO APPARENT IN VESICLE RICH
ZONES, VEINING IS PARALLEL TO CONTACT AND MAY BE
RELATED TO REIDEL SHEARS ABOVE IN VESICLE POOR ZONE;
Comments : MEDIUM GREY (N5);
Vesicles : PRINCIPAL FEATURE IS CONCENTRATION OF VESICLES
INTO DISCRETE BANDS SEPARATED BY ZONES WITH MINOR
VESICLES, DISTINCT GRADING ALSO APPARENT IN
VESICLE RICH ZONES;
Groundmass : PYROXENE
PLAGIOCLASE
LATHS;
Leg : 81 Top/Bottom Interval(mm): 0/ 550 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 672.05
Core: 58 Top of Core Depth (m) : 668.50
Sect: 3 Top of Section Depth(m): 671.50
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 58-2;
Piece No. : PCES 1 (2-6), 2 (9-16), 3 (19-26), 4 (29-36),
5 (37-44), 6 (47-53);
Texture : PHYRIC, ZONING INTO VESICLE RICH/POOR ZONES;
Structure : PCE 3 MAY BE SLICKENSIDED(?), DISTINCT RIEDEL SHEAR
PATTERN DEVELOPED IN PCES 2B+6 AND ARE ALWAYS FOUND
IN VESICLE FREE ZONES;
Comments : MEDIUM GREY (N5), CURVATURE OF ZONE BOUNDARIES
STRONGLY SUGGEST CONTEMPORANEOUS FORMATION;
Vesicles : MAJOR LITHOLOGIC VARIATION IS PRESENT WITHIN AND
BETWEEN VESICLE RICH ZONES;
Leg : 81 Top/Bottom Interval(mm): 0/1470 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 674.47
Core: 59 Top of Core Depth (m) : 673.00
Sect: 1 Top of Section Depth(m): 673.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 1 (2-6), 2 (7-10), 3 (13-15), 4 (17-21),
5 (24-27), 6 (29-34), 7 (36-40), 8 (42-47),
9 (49-60), 10 (62-67), 11 ((69-72), 12 (74-76),
13 (78-80), 14 (83-85), 15 (89-90), 16 (91-96),
17 (98-102), 18 (104-106), 19 (99-117),
20 (119-122), 21 (125-128), 22 (132-135),
23 (139-140), 24 (144-147);
Texture : PHYRIC, INCREASE IN VESICLE SIZE AS GO DOWN CORE,
PLAG AND PYX ARE LOCALLY GLOMEROPHYRIC;
Structure : FOLIATION IS ABSENT;
Comments : MEDIUM GREY (N5);
Vesicles : PRINCIPAL VARIATION DOWNCORE IS AN INCREASE IN
THE SIZE OF THE VESICLES AND IN THE PROPORTION OF
OPEN VESICLES, THE CHANGE OCCURS AT CA 100CM,
ABOVE 100CM SMALL VESICLES WITH LARGE OPEN
VESICLES SPARSE, BELOW 100CM MORE OPEN LARGE
VESICLES;
Leg : 81 Top/Bottom Interval(mm): 0/ 300 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 674.80
Core: 59 Top of Core Depth (m) : 673.00
Sect: 2 Top of Section Depth(m): 674.50
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 59-1;
Piece No. : PCES 1 (2-8), 2 (11-15), 3 (17-23), 4 (25-28);
Texture : PHYRIC VESICULAR BASALT, OCCASIONAL GLOMEROPHYRES
COARSER IN GRAIN-SIZE THAN IN PCE 5;
Comments : MED GREY (N5);
Vesicles : VESICLES LINED WITH BLACK WITH LIGHT OLIVE
(10Y5/4) CORE;
Leg : 81 Top/Bottom Interval(mm): 300/ 350 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 674.85
Core: 59 Top of Core Depth (m) : 673.00
Sect: 2 Top of Section Depth(m): 674.80
LITHOLOGY: BASALT;
Piece No. : PCE 5 (30-35);
Texture : FINE-GRAINED BASALT WITH GLOMEROPHYRES;
Comments : MEDIUM GREY, COULD BE BASE OF FLOW;
Vesicles : SPARSE LARGE VESICLES;
Leg : 81 Top/Bottom Interval(mm): 350/ 450 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 674.95
Core: 59 Top of Core Depth (m) : 673.00
Sect: 2 Top of Section Depth(m): 674.85
LITHOLOGY: VESICULAR BASALT;
Piece No. : PCES 6 (35-45), 7 (46-54), 8 (55-60);
Structure : MICROFRACTURING PRESENT;
Alteration : PYX COULD BE ALTERED- REDDENED AT EDGES;
Comments : PCE 6 COULD BE TOP OF FLOW(?);
Vesicles : Size(mm): 1-2 + 30 Percent:
CHARACTERISED BY LARGE (3CM) OPEN VESICLES LINED
WITH DARK GREENISH GREY (5GY4/1), SMALLER VESICLES
(1-2MM) INFILLED WITH BLACK (N2) AND REDDENED AT
EDGES;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
PYX ARE REDDENED (ALTERED);
Leg : 81 Top/Bottom Interval(mm): 450/1300 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 675.80
Core: 59 Top of Core Depth (m) : 673.00
Sect: 2 Top of Section Depth(m): 674.95
LITHOLOGY: PHYRIC VESICULAR BASALT;
Piece No. : PCES 9 (62-65), 10 (67-76), 11 (77-90),
12A (92-100), 12B (100-130);
Texture : PHYRIC, SPARSE GLOMEROPHYRES OF PLAG AND PYX;
Structure : INCLINED FRACTURE (50 DEGREES)- NOT SLICKENSIDED;
SOME VEIN FILLED FRACTURES PRESENT;
Comments : MEDIUM DARK GREY (N4) GRADING DOWNWARD INTO MEDIUM
GREY (N5);
Vesicles : Size(mm): 20 Percent:
PCE 10 HAS SMALL BLACK (N2) VESICLES AND LARGE 2CM
VUGS, VUGS LINED WITH BLACK AND HAVE AMYGDALOIDAL
STRUCTURE OF LIGHT BLUISH GREY (5B7/1) AND PALE
OLIVE (10Y6/2);
Size(mm): 30 Percent:
VUGS BECOME SPARSE IN PCE 11, BELOW THIS LEVEL
SPARSE 3CM VESICLES COMMON, SOME VESICLES ALIGNED
ALONG VEIN FILLED FRACTURES, LARGE VESICLES HAVE
BLACK (N2) LINING WITH CORE OF INTERGROWN LIGHT
BLUISH GREY (5B7/1) AND PALE OLIVE (10Y6/2) TO
LIGHT OLIVE (10Y5/4) AND BLACK (N2);
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
SPARSE GLOMEROPHYRES IN GROUNDMASS;
Leg : 81 Top/Bottom Interval(mm): 0/1350 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 677.35
Core: 59 Top of Core Depth (m) : 673.00
Sect: 3 Top of Section Depth(m): 676.00
LITHOLOGY: PHYRIC VESICULAR BASALT;
CONTINUED FROM 59-2;
Piece No. : PCES 1A (0-21), 1B (21-34), 2 (35-42), 3A (45-50),
3B (50-62), 3C (64-71), 4 (74-83), 5 (85-90),
6A (92-95), 6B (95-100), 6C (100-108),
7 (111-120), 8A (122-127), 8B (130-135);
Texture : PHYRIC, BRECCIATED BASALT FRAGMENTS OCCUR ALONG
FAULT IN PCES(3B,3C,4,6A), OCCASIONAL PLAG PHENOS;
Structure : THE MAJOR STRUCTURE BELOW 15CM IS A MARKED
HORIZONTAL FOLIATION THAT PERSISTS DOWN TO THE BASE
OF THE SECTION, VERTICAL FOLIATION OCCURS IN PCE 7,
PCES(3B,3C,4,6A) HAVE A FAULT, VEIN INFILL ALONG
FAULT CONSISTS OF BLACK LINING WHICH HAS PENETRATED
HOST ROCK- ELONGATE ANGULAR LIGHT BLUISH GREY,
FIBROUS LIGHT OLIVE MINERAL (10Y5/4) ALONG
SLICKENSIDED FACE, INCLINATION OF FAULT IS 80
DEGREES, SLICKENSIDES ARE 70 DEGREES TO CUT FACE OF
CORE;
Comments : MEDIUM GREY (N5);
Vesicles : Size(mm): 2-10 Percent:
LARGE VESICLES (0.2CM-1CM) PREDOMINATE DOWN TO
15CM AND ARE FILLED WITH BLACK LINING WITH DUSKY
GREEN (5G3/2) CORE OF INTERGROWTH OF BLACK (N2),
LIGHT BLUISH GREY (5B7/1) AND LIGHT OLIVE GREY
(5Y6/1), BELOW THIS LEVEL VESICLES OCCUR
SPORADICALLY;
Phenocrysts: PLAGIOCLASE
OCCASIONAL PLAG PHENOCRYSTS;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
SMALL;
Leg : 81 Top/Bottom Interval(mm): 0/1300 Analyst: Roberts, D. .
Hole: 553A Sample Midpoint (m) : 678.80
Core: 59 Top of Core Depth (m) : 673.00
Sect: 4 Top of Section Depth(m): 677.50
LITHOLOGY: PHYRIC BASALT;
CONTINUED FROM 59-3;
Piece No. : PCES 1A (0-10), 1B (10-21), 2 (22-26), 3 (27-36),
4A (40-47), 4B (47-53), 5A (55-66), 5B (65-67),
5C (67-76), 5D (76-78), 6A (80-95), 6B (94-110),
6C (110-120), 6D (120-130);
Texture : PHYRIC, 1CM LIGHT BLUISH GREY BLEBS WITH PALE OLIVE
(10Y6/2) MINERAL IN THE INTERSTICES, BLACK (N2)
MINERAL ALSO PRESENT AS PHENOCRYST WITHIN LIGHT
BLUISH GREY;
Structure : PRINCIPAL VARIATION IS IN THE PRESENCE OF SUB-
HORIZONTAL FOLIATION, FOLIATION FIRST APPEARS IN
PCE 1B BECOMING MOST PRONOUNCED (3MM SPACING) IN
PCES 5 AND UPPER PCE 6 TO LESS PRONOUNCED IN PCES
6C+6D, PCE 4B HAS VEIN INCLINATION OF 70 DEGREES,
SOME SUGGESTION THAT BLACK LINING WITH THIN GREY
(N7) LAYERS HAS BEEN FRACTURED AND PARTLY
INCORPORATED INTO BLUISH GREY AREA, ANGULAR BLACK
(N2) FRAGMENTS WITH PENETRATION OF BLUISH GREY INTO
BLACK LINING;
Comments : MEDIUM GREY (N5), BLACK LINING HAS THIN GREY LAYERS;
Vesicles : Size(mm): <1 Percent:
VESICLES ARE MINOR AND ARE TYPICALLY LESS THAN 1MM
IN SIZE ALTHOUGH THEY OCCUR THROUGHOUT, LARGE
VESICLES REAPPEAR IN PCES 6C+6D, THE LARGEST VUGGY
VESICLE HAS 1CM LIGHT BLUISH GREY BLEBS WITH PALE
OLIVE (10Y6/2) MINERAL IN THE INTERSTICES, LARGE
(3MM) VUGGY VESICLE IN PCES 6C+6D;
Groundmass : PLAGIOCLASE
LATHS;
PYROXENE
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