Leg : 33 Top/Bottom Interval(mm): 1020/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 998.00
Core: 31 Top of Core Depth (m) : 996.50
Sect: 1 Top of Section Depth(m): 997.52
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (102-111), 2 (111-122), 3 (123-127),
4 (127-130), 5 (131-135), 6 (136-148);
Texture : APHYRIC, TEXTURE IS DIABASIC - INTERSERTAL, PLAG
CONSISTING MOSTLY OF LATHS OF DIMENSIONS 0.3 X 1 MM
+ A FEW AT 0.6 X 2 MM, A FEW PLATES OF PYROXENE
AND GLASS INTERSTITIAL;
Alteration : CORE IS ALL PARTIALLY ALTERED AND APPEARS TO
BECOME MORE ALTERED DOWNWARD IN SECTION, PLAG IS
FIFTY PERCENT ALTERED TO SERICITE ESPECIALLY
DOWN CENTRAL PART OF LATHS, GLASS ENTIRELY
ALTERED TO CLAY;
Comments : GREYISH GREEN TO DARK GREENISH GREY, APPEARS TO BE
SAME FLOW UNIT AS THAT OF THE BASE OF CORE 30
SECTION 2, UNCUT;
Vesicles : Size(mm): 0.5-1.5 Percent: 1-2
Location: Filling: CALCITE, ZEOLITE
VESICULAR, FINELY VESICULAR;
Groundmass : PLAGIOCLASE
Size(mm): 0.3 X 1
LATHS OF 0.3 X 1 MM + A FEW AT 0.6 X 2 MM, PLAG
50 PERCENT ALTERED TO SERICITE;
PYROXENE
GLASS
INTERSTITIAL, GLASS ENTIRELY ALTERED TO CLAY;
Replacement: CALCITE
IN VESICLES;
ZEOLITE
IN VESICLES;
SERICITE
Minerals Replaced: PLAG
PLAG 50 PERCENT ALTERED TO SERICITE;
CLAY
Minerals Replaced: GLASS
GLASS ENTIRELY ALTERED TO CLAY;
Leg : 33 Top/Bottom Interval(mm): 870/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1007.50
Core: 32 Top of Core Depth (m) : 1006.00
Sect: 1 Top of Section Depth(m): 1006.87
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1A (87-95), 1B (93-97), 2 (99-114),
3 (115-121), 4 (122-126), 5 (126-133),
6 (134-150);
Texture : APHYRIC, TEXTURE INTERGRANULAR, PLAG IN STUBBY LATHS
OF 2-4 MM, CPX AVG GRAIN SIZE IS ABOUT 4 MM, DIFFERS
FROM BASALT IN CORES 30-31 AS IT MAY BE CHILLED TOP
OF FLOW SEEN IN CORE 33 SECTION 2;
Structure : ONE SPOTTY CALCITE VEIN OBSERVED IN PCE 6 AT ABOUT
45 DEGREES TO CORE;
Alteration : PLAG RELATIVELY FRESH, CPX 75 PERCENT ALTERED TO
CHLORITIC AGGREGATES, CONSIDERABLE CALCITE
REPLACEMENT;
Comments : DARK GREENISH GREY, AT 87 CM NEAR TOP OF NEW FLOW
UNIT, UNCUT;
Vesicles : Size(mm): 0.5-2 Percent: 1-5
Location: Filling: CALCITE
Shape : CIRCULAR
VESICULAR, ARRANGED IN BANDS PERPENDICULAR TO
CORE (SEE PCES 2 + 3 + 6), CIRCULAR AND
UNFLATTENED, VESICLES LARGELY OPEN AND UNFILLED,
A FEW CONTAIN CALCITE;
Groundmass : PLAGIOCLASE
Size(mm): 2-4
IN STUBBY LATHS OF 2-4 MM;
CLINOPYROXENE
Size(mm): 4
CPX GRAIN SIZE IS ABOUT 4MM;
Replacement: CHLORITE
Minerals Replaced: CPX
CPX ALTERED TO CHLORITIC AGGREGATES;
CALCITE
CONSIDERABLE CALCITE REPLACEMENT, CALCITE VEIN ON
PCE 6, A FEW VESICLES CONTAIN CALCITE;
Leg : 33 Top/Bottom Interval(mm): 0/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1009.00
Core: 32 Top of Core Depth (m) : 1006.00
Sect: 2 Top of Section Depth(m): 1007.50
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (1-4), 2 (5-10), 3 (10-20), 4 (20-22),
5 (22-24), 6 (24-57), 7 (58-63), 8 (63-100),
9 (101-104), 10 (105-110), 11 (105-110),
12 (110-112), 13 (113-119), 14 (120-123),
15 (123-139), 16 (141-148);
Texture : APHYRIC, UPPER 9 CM APPEARS IDENTICAL TO BASALT IN
CORE 32 SECTION 1 - SAME DESCRIPTION APPLIES, BELOW
9 CM BASALT BECOMES STEADILY BUT SLOWLY COARSER
GRAINED, COARSEST PART OF FLOW UNIT OCCURS BETWEEN
50 AND 90 CM, FINALLY GRAIN SIZE DECREASES SLIGHTLY
AT 123 CM, IN COARSEST PORTION TEXTURE IS DIABASIC -
TRACHYTIC WITH FELDSPAR LATHS STRONGLY ALIGNED
HORIZONTALLY (FELDSPAR AVERAGE 4 X 2 MM WITH A FEW
SEEN AS LONG AS 5 MM), PYROXENE INTERSTITIAL AND
LITTLE IF ANY GLASS APPEARS TO BE PRESENT IN THE
COARSEST PART, BENEATH CONTACT AT 123 CM IS 10 CM
OF BASALT WHICH IS EXTREMELY FINE GRAINED AND
PROBABLY GLASS RICH, BELOW THIS 10 CM BORDER BASALT
REMAINS APHYRIC AND COARSENS, ALSO BELOW THIS 10 CM
BORDER THE PLAG ARE LATHS (O.2 X 1MM) + THE
TEXTURE IS DIABASIC-TRACHYTIC;
Alteration : UPPER 9 CM APPEARS IDENTICAL TO BASALT IN CORE 32
SECTION 1 HOWEVER BELOW THAT IT APPEARS TO BE LESS
ALTERED DOWN SECTION, COARSEST PART OF FLOW UNIT
OCCURS BETWEEN 50 AND 90 CM AND HERE THE PLAG IS
FRESH AND THE PYROXENES SEEM TO BE ABOUT HALF
ALTERED TO CHLORITIC MATERIAL, BENEATH CONTACT AT
123 CM IS PROBABLY GLASS RICH AND ALMOST
COMPLETELY ALTERED;
Comments : UPPER 9 CM APPEARS IDENTICAL TO BASALT IN CORE 32
SECTION 1 - SAME DESCRIPTION APPLIES, BETWEEN 50
AND 90 CM IS DARK GREENISH GREY, CONTACT AT 123 CM
IS SHARP AND COMPLETELY UNWEATHERED, BENEATH CONTACT
IS 10 CM OF BASALT WHICH IS MEDIUM BLUISH GREY,
BELOW 1O CM BORDER BASALT THE COLOR RETURNS TO DARK
GREENISH GREY, UNCUT, PCE 9 IS NOT SHOWN ON THE
GRAPHIC REPRESENTATION BUT IS PRESENT ON THE ACTUAL
CORE;
Vesicles : BELOW 9 CM IT IS VUGGY RATHER THAN VESICULAR;
Size(mm): TO 5 Percent: 5-10
BETWEEN 50 AND 90 CM VUGS ARE OPEN UNFILLED AND
SHOW ONLY GROUNDMASS TEXTURE, THE VUGS ARE AS
LARGE AS 5 MM WITH AVERAGE OF 2 MM;
Size(mm): Percent: 0
BELOW CONTACT AT 123 CM IS 10 CM OF BASALT WHERE
IT IS DENSE WITH NO VESICLES OR VUGS;
Size(mm): 1.0 Percent:
BELOW THE 10 CM BORDER BASALT THE ROCK BECOMES
VUGGY WITH OPEN VUGS AVERAGING ABOUT 1 MM;
Groundmass : FELDSPAR
Size(mm): 0.4 X 2
LATHS AVERAGE 0.4 X 2 MM AND A FEW SEEN AS LONG AS
5 MM;
GLASS
PYX
PYX INTERSTITIAL AND LITTLE IF ANY GLASS APPEARS
TO BE PRESENT (50-90 CM), PYROXENES SEEM TO BE
ABOUT HALF ALTERED TO CHLORITIC MATERIAL;
PLAGIOCLASE
PLAG FRESH, BELOW 10 CM BORDER PLAG IS LATHS
OF 0.2 X 1 MM;
Replacement: CHLORITE
Minerals Replaced: PYX
PYROXENES SEEM TO BE ABOUT HALF ALTERED TO
CHLORITIC MATERIAL;
Leg : 33 Top/Bottom Interval(mm): 0/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1010.50
Core: 32 Top of Core Depth (m) : 1006.00
Sect: 3 Top of Section Depth(m): 1009.00
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (1-21), 2 (21-23), 3 (23-30), 4 (30-34),
5 (34-39), 6 (37-41), 7 (30-36), 8 (39-106),
9 (106-121), 10 (122-129), 11 (124-129),
12 (128-130), 13 (130-145), 14 (145-150);
Texture : APHYRIC, UPPER 6 CM APPEARS IDENTICAL TO THAT
DESCRIBED AT BASE OF CORE 32 SECTION 2 AND FROM
6-18 CM BASALT GRADUALLY COARSENS, FROM 18-45 CM
BASALT BECOMES FINE GRAINED, FROM 45-107 CM THE
BASALT IS COARSE GRAINED, BETWEEN 107-121 CM IT
GRADUALLY BECOMES MEDIUM GRAINED, COARSEST PART IS
AT FLOW UNIT (45-107 CM) - HERE TEXTURE IS DIABASIC-
TRACHYTIC WITH FELDSPARS LATHS STRONGLY LINED
HORIZONTALLY, FELDSPARS AVERAGE 0.3 X 4 MM AND
SOMETIMES REACH 0.3 X 15 MM, PYROXENE INTERSTITIAL
AND LITTLE IF ANY GLASS PRESENT, FROM 121-131 CM
BASALT APHYRIC NEARLY APHANITIC + GRADES DOWNWARD TO
COARSER;
Structure : CRACK ON PCE 8;
Alteration : FROM 45-107 CM PLAG IS FRESH AND PYX IS
CONSIDERABLY ALTERED, FROM 121-131 CM BOTH PLAG
AND PYX APPEAR TO BE CONSIDERABLY ALTERED;
Comments : UPPER 6 CM APPEARS IDENTICAL TO THAT DESCRIBED AT
BASE OF CORE 32 SECTION 2, THE COARSEST PART OF THE
FLOW UNIT (45-107 CM) IS MEDIUM GREENISH GREY,
FROM 121-131 CM IT IS MEDIUM BLUISH GREY THEN COLOR
CHANGES TO DARK GREENISH GREY, AT 120 CM A PROBABLE
TOP OF NEW FLOW UNIT;
Vesicles : Size(mm): TO 3 Percent:
FROM 6-18 CM BASALT BECOMES VUGGY WITH VUGS
AVERAGING 1 MM AND REACHING AS LARGE AS 3 MM;
Size(mm): Percent: 0
FROM 18-45 CM BASALT LOSES VUGS;
Size(mm): 2.0 Percent: 10-15
FROM 45-107 CM BASALT IS VUGGY, VUGS FLATTENED
AND AVERAGE 2 MM AND REACH 3 X 5 MM + ARE
UNFILLED WITH NO CRYSTAL LININGS, VUGS REACH
MAXIMUM DEVELOPMENT BETWEEN 45-75 CM;
Size(mm): 0.5 Percent:
FROM 121-131 CM BASALT CONTAINS A FEW O.5 MM
ROUND VESICLES - DENSE PLUS PROBABLY CONTAINS
ALTERED GLASS, BASALT IS SOMEWHAT VUGGY MUCH LIKE
THAT AT TOP OF SECTION;
Groundmass : FELDSPAR
Size(mm): 0.3 X 4
LATHS STRONGLY LINED HORIZONTALLY, FELDSPARS AVG
0.3 X 4 MM SOMETIMES REACHING 0.3 X 15 MM;
PYROXENE
INTERSTITIAL, CONSIDERABLY ALTERED;
PLAGIOCLASE
PLAG FRESH (45-107 CM), PLAG CONSIDERABLY
ALTERED ( FROM 121 CM TO END);
GLASS
PYX INTERSTITIAL AND LITTLE IF ANY GLASS PRESENT
(45-107 CM), ROUND VESICLES PROBABLY CONTAIN
ALTERED GLASS;
Leg : 33 Top/Bottom Interval(mm): 0/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1012.00
Core: 32 Top of Core Depth (m) : 1006.00
Sect: 4 Top of Section Depth(m): 1010.50
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (0-6), 2 (7-46), 3 (47-51), 4 (47-51),
5 (49-66), 6 (66-82), 7 (81-92), 8 (92-99),
9 (99-104), 10 (105-119), 11 (119-130),
12 (130-135), 13 (135-139), 14 (135-139),
15 (139-150), 16 (147-150);
Texture : FROM 6-49 CM BASALT IS COARSE AND VUGGY MUCH LIKE
THAT DESCRIBED IN THE INTERVAL 45-107 CM IN CORE 32
SECTION 3, FELDSPAR LATHS LIE AT ANGLES UP TO 15
DEGREES FROM PERPENDICULAR TO SECTION, FINE GRAINED
AREA BETWEEN 50 AND 56 CM, FROM 56-150 CM BASALT
COARSENS TO MEDIUM GRAINED, APHYRIC, TEXTURE
DIABASIC - LOCALLY TRACHYTIC, FELDSPAR ALIGNMENT
MUCH LESS PRONOUNCED THAN IN INTERVAL 6-49 CM,
FELDSPARS AVERAGE 0.2 X 0.8 MM WITH A FEW CRYSTALS
AS LONG AS 2 MM, PYROXENES INTERSTITIAL AND AT LEAST
PARTIALLY ALTERED;
Structure : FRACTURES IN PCES 9 AND 11;
Alteration : PYROXENES INTERSTITIAL AND AT LEAST PARTIALLY
ALTERED (56-120 CM);
Comments : UPPER 6 CM APPEARS IDENTICAL TO THAT DESCRIBED AT
THE BASE OF SECTION 2, POSSIBLE TOP OF FLOW UNIT AT
50 CM, MEDIUM GREENISH GREY (56-120 CM), FROM 47-56
CM BASALT IS MUCH LIKE THAT DESCRIBED FROM 18-45 CM
IN CORE 32 SECTION 3, UNCUT;
Vesicles : FROM 6-49 CM BASALT IS COARSE AND VUGGY MUCH LIKE
THAT DESCRIBED IN THE INTERVAL 45-107 CM IN CORE
32 SECTION 3 WITH SOME EVEN VUGGIER;
Size(mm): 1.5 Percent: 5
56-120 CM IS LOCALLY VUGGY WITH 0-10 PERCENT
AVERAGING ABOUT 5 PERCENT, VUGS AVERAGE 1.5 MM
AND REACH 2 X 4 MM AND ARE LOCALLY FLATTENED WITH
NO LININGS;
Groundmass : FELDSPAR
Size(mm): 0.2 X 0.8
FELDSPAR LATHS LIE AT ANGLES UP TO 15 DEGREES FROM
PERPENDICULAR (6-49 CM), FELDSPAR ALIGNMENT FROM
56-120 CM IS MUCH LESS PRONOUNCED THAN IN INTERVAL
6-49 CM, FELDSPARS AVERAGE 0.2 X 0.8 MM WITH A FEW
CRYSTALS AS LONG AS 2 MM;
PYROXENE
PYROXENES INTERSTITIAL AND AT LEAST PARTIALLY
ALTERED (56-120 CM);
Leg : 33 Top/Bottom Interval(mm): 740/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1017.00
Core: 33 Top of Core Depth (m) : 1015.50
Sect: 1 Top of Section Depth(m): 1016.24
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (74-80), 2 (81-89), 3 (87-90), 4 (88-90),
5 (91-97), 6 (97-101), 7 (100-107), 8 (109-123),
9 (124-128), 10 (129-134), 11 (134-140),
12 (134-140), 13 (144-147), 14 (140-143),
15 (147-150);
Texture : APHYRIC, VERY FINE GRAINED TO APHANITIC, TEXTURE IS
DIABASIC TO INTERSERTAL;
Alteration : FELDSPAR APPEARS PARTLY FRESH, SUSPECT PYROXENES
AND GLASS BADLY ALTERED, ALTERED BASALT;
Comments : MEDIUM BLUISH GREY, BARES LITTLE RESEMBLANCE TO FLOW
ALTOGETHER, UNCUT;
Vesicles : Size(mm): TO 1.5 Percent: 1-5
Location: Filling: CALCITE, ZEOLITE
VESICULAR, AVG OF 3 PERCENT, AVERAGE 0.5 MM IN
DIAMETER AND RANGE UP TO 1.5 MM, ALL ARE FILLED
WITH CALCITE AND ZEOLITE;
Groundmass : FELDSPAR
APPEARS FRESH;
PYROXENE
GLASS
SUSPECT PYX AND GLASS BADLY ALTERED;
Replacement: CALCITE
IN VESICLES;
ZEOLITE
IN VESICLES;
Leg : 33 Top/Bottom Interval(mm): 90/1500 Analyst: Jackson, E.D.
Hole: 315A Sample Midpoint (m) : 1026.50
Core: 34 Top of Core Depth (m) : 1025.00
Sect: 1 Top of Section Depth(m): 1025.09
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCES 1 (9-11), 2 (11-18), 3 (18-19), 4 (19-21),
5 (19-21), 6 (19-21), 7 (19-21), 8 (19-21),
9A (21-30), 9B (30-35), 10 (35-39), 11 (39-42),
12 (43-45), 13 (43-45), 14 (43-45), 15 (45-47),
16 (45-47), 17 (49-51), 18 (48-50), 19 (50-62),
20 (62-67), 21 (67-82), 22 (82-86), 23 (83-86),
24 (86-88), 25 (86-90), 26 (89-95), 27 (95-106),
28 (105-110), 29 (110-112), 30 (111-115),
31 (112-116), 32 (116-126), 33 (125-127),
34 (129-134), 35 (128-134), 36 (135-137),
37 (138-141), 38 (142-144), 39 (144-146),
40 (145-149);
Texture : APHYRIC, VERY FINE GRAINED, DIABASIC TEXTURE,
FELDSPAR LATHS OF 0.1 X 0.4 MM, MATERIAL FROM 24-34
CM IS APHANITIC;
Alteration : FELDSPAR APPEARS FRESH, SUSPECT PYROXENES AND
GLASS BADLY ALTERED;
Comments : DARK GREENISH GREY, MATERIAL FROM 9-24 CM APPEARS
TO BE THE SAME AS CORE 33 SECTION 4, MATERIAL FROM
24-34 CM IS MEDIUM BLUISH GREY, SUSPECT A NEW FLOW
UNIT HERE BETWEEN 24-34 CM AND CONTACT IS COMPLETELY
SHARP;
Vesicles : Size(mm): 1.0 Percent: 0-10
Location: Filling: CALCITE, ZEOLITE
VESICULAR, AVG OF 5 PERCENT, AVERAGE SIZE IS
1 MM BUT SOME FLATTENED UP TO 2 X 3 MM, ALL
VESICLES FILLED WITH CALCITE AND OR ZEOLITES;
Groundmass : FELDSPAR
Size(mm): 0.1 X 0.4
FELDSPAR LATHS AVERAGING 0.1 X 0.4 MM, FELDSPAR
APPEARS FRESH;
GLASS
PYROXENE
SUSPECT PYROXENES AND GLASS BADLY ALTERED;
Replacement: CALCITE
IN VESICLES;
ZEOLITE
IN VESICLES;
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