Leg : 34 Top/Bottom Interval(mm): 0/1500 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 113.00
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 111.50
LITHOLOGY: BASALT;
Piece No. : PCE 1 (51-56), 2 (58-64);
Texture : COOLING UNIT GRADES FROM FINE-GRAINED and SPHERULITIC
TO FINELY VARIOLITIC DOWNWARD TO AN INCOMPLETE BLACK
GLASSY SELVAGE;
Structure : VEINS INCLUDE CARBONATE and RED-BROWN SMECTITE;
Comments : THIS IS THE FIRST OF THREE COOLING UNITS THAT MAKE
UP SEC 13-1, COLOR GRADES FROM MEDIUM GRAY TO DARK
BROWNISH GRAY DOWNWARD TO BLACK, GLASS AT 63-65CM
MARKS A FLOW UNIT BOUNDARY---PROBABLY A PILLOW RIND,
SKETCHES OF MOST PIECES AVAILABLE ON MICROFILMED
SHIPBOARD DESCRIPTION;
Phenocrysts: PLAGIOCLASE ( TO 1%)
OLIVINE
MICROPHENOCRYSTS INCLUDE PLAG and EUHEDRAL TO
SKELETAL OLIVINE;
Groundmass : GLASS
GLASSY ZONE AT 63-65CM;
Replacement: PALAGONITE
MINOR ORANGE and COLORLESS, IN LOWER PART OF
INTERVAL;
SMECTITE
Minerals Replaced: OLIVINE
VEINS, OLIVINE COMMONLY ALTERED TO YELLOW SMECTITE
and FE.OXIDE;
FERROUS OXIDE
Minerals Replaced: OLIVINE
CARBONATE
VEINS;
Leg : 34 Top/Bottom Interval(mm): 0/1500 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 113.00
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 111.50
LITHOLOGY: BASALT;
Piece No. : PCE 3 (66-72), 4 (73-82), 5 (83-91), 6 (93-95),
7 (97-103), 8 (104-114), 9 (116-124), 10 (125-131);
Texture : VERY FINE-GRAINED, VARYING TO APHANITIC AT THE BASE,
NO GLASS RECOVERED, VERY FINE VARIOLITIC TO
INTERGRANULAR;
Structure : VEINS INCLUDE CALCITE and POSSIBLY MINOR ARAGONITE &
YELLOW and GREEN and BROWN SMECTITE, THICK VERTICAL
CALCITE VEIN (UP TO 3MM) BELOW 97CM ENCLOSES SPALLS
OF BASALT AND APPEARS TO HAVE FILLED AN OPEN JOINT;
Comments : COLOR IS MEDIUM TO DARK YELLOWISH GRAY, THIS IS THE
SECOND COOLING UNIT IN SEC 13-1;
Vesicles : DIKTYTAXITIC VUGS OCCUR BELOW 83CM;
Phenocrysts: PLAGIOCLASE ( TO 1%)
OLIVINE
MICROPHENOCRYSTS VARY FROM ALMOST NONE TO ABOUT
1%, MOST ABUNDANT AT TOP and BOTTOM;
Replacement: SMECTITE
Minerals Replaced: OLIVINE
CARBONATE
Minerals Replaced: OLIVINE
OLIVINE ALMOST WHOLLY ALTERED TO SMECTITE and MINOR
CARBONATE;
CALCITE
VEINS;
FERROUS OXIDE
STAINS;
MANGANESE OXIDE
SPOTS and DENDRITES;
ARAGONITE
VEINS;
Leg : 34 Top/Bottom Interval(mm): 0/1500 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 113.00
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 111.50
LITHOLOGY: PLAG-OLIVINE SPARSELY MICROPHYRIC BASALT;
Piece No. : PCE 11 (133-148);
Texture : SPARSELY MICROPHYRIC, FINE-GRAINED;
Structure : CUT BY ONE CALCITE VEIN;
Comments : COLOR IS MEDIUM TO DARK YELLOWISH GRAY, ALL PIECES
IN SECTION ARE PARTS OF JOINT BLOCKS IN WHICH
SHARPLY BOUNDED and DIFFUSION-CONTROLLED COLOR ZONES
REFLECT BOUNDING JOINTS--MOST OF WHICH LAY OUTSIDE
THE RECOVERED CORE, THE COLORS ARE DARKER AND/OR
YELLOWER OR BROWNER NEARER THE JOINTS, THIS INTERVAL
IS THE THIRD COOLING UNIT IN SEC 13-1;
Groundmass : PLAGIOCLASE ( 2.7%)
OLIVINE
2.7% PLAG and ALTERED OLIVINE;
Replacement: CALCITE
Leg : 34 Top/Bottom Interval(mm): 510/ 560 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.06
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.01
LITHOLOGY: BASALT;
Piece No. : PCE 1 (51-56);
Texture : FINE-GRAINED;
Structure : UNJOINTED;
Comments : ROTATED DURING DRILLING--ORIENTATION UNKNOWN,
CONSISTS OF THREE ROCK TYPES: 1-DARK BROWNISH GRAY
(10YR 3/1) WITH MESOSTASIS ALTERED TO RED-BROWN
PALAGONITE MATERIAL- 2-MEDIUM GRAY (2.5Y 5/0)
RELATIVELY FRESH WITH SLIGHT YELLOW STAIN IN SOME
PATCHES OF MESOSTASIS- 3-MEDIUM GRAY (5Y 4/1) OR
(5Y 4/2) WITH MODERATE YELLOW TO BROWN BUT RARELY
RED STAIN IN MESOSTASIS;
Replacement: PALAGONITE
Leg : 34 Top/Bottom Interval(mm): 580/ 640 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.14
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.08
LITHOLOGY: PLAG MICROPHYRIC BASALT;
GLASS;
Piece No. : PCE 2 (58-64);
Texture : MICROPHYRIC;
Structure : STRUCTURALLY THE ROCK SHOWS INCIPIENT COLUMNAR
JOINTING BEST SEEN ON BOTTOM SURFACE - ONLY THOSE
JOINTS PRESENTLY BOUNDING THE INTERIOR SURFACE OF
THE CORE and THE JOINT PASS VERTICALLY THROUGH THE
ENTIRE LENGTH OF PCE 2 - THE OTHERS DIE OUT WITHIN
2-4CM ABOVE THE BOTTOM, CONTAINS WHITE CALCITE
VEINS;
Comments : HALF CYLINDER (SPLIT CORE) THROUGH LOWER GLASSY
SELVAGE OF TOPMOST FLOW UNIT, INTERIOR SURFACE IS
VERTICAL LIGHT GRAY JOINT PARTIALLY COATED BY 0.1MM-
THICK WHITE CALCITE VEIN AND LIGHTLY STAINED YELLOW
ALONG UPPER EDGE, GLASS GRADES RAPIDLY UPWARD TO
SPHERULITE LAYER WITH INTERSTITIAL GLASS WHICH IS
GENERALLY FRESH BUT ALTERED TO YELLOW-BROWN
PALAGONITE ON EXPOSED SURFACE ON BOTTOM - THIS GLASS
DISAPPEARS RAPIDLY UPWARD GIVING A CONTINUOUS LAYER
OF SPHERULITES EXPOSED ON THE DARK YELLOWISH GRAY
SURFACE "A" (2.5Y 3/0), BY GRADUAL TEXTURAL and COLOR
TRANSITIONS THE ROCK GRADES UPWARD THROUGH AN
APHANITIC (PROBABLY FINELY VARIOLITIC) MATERIAL
EXPOSED ON DARK GRAY SURFACE "B" (5Y 2.5/1) TO THE
APHANITIC TO VERY FINE-GRAINED BASALT ON TOP SURFACE
WHICH IS DARK GRAY (5Y 3/0) ON SURFACE "C" TO ALMOST
BLACK (2.5YR 4/0) ON "D", SURFACE D IS RESTRICTED
TO A ZONE ABOUT 5MM WIDE BETWEEN PROMINENT JOINTS -
INCLUDING THAT WHICH IS PARTLY VEIN-COATED and THE
SHARP BOUNDARY BETWEEN C&D, D IS PROBABLY SOMEWHAT
MORE ALTERED THAN C BUT IS OTHERWISE EQUIVALENT, THE
JOINTS (MARKED "X" ON SHIPBOARD SKETCH) HAVE PARTIAL
RED-BROWN STAINS OR COATS, THE BOTTOM SURFACE &
LOWERMOST VERTICAL JOINTS (MARKED "Y") ARE COATED
WITH A PAPER-THIN BLUE TRANSLUCENT FILM--THE FILM
SPALLS OFF EASILY and IS ISOTROPIC and LIGHT BROWN IN
TRANSMITTED LIGHT and HAS A REFRACTIVE INDEX OF 1.5 OR
SLIGHTLY LESS--IT IS PROBABLY COLORLESS PALAGONITE
FORMED IN AN ANOXIC ENVIRONMENT AFTER BURIAL (THIS
INTERPRETATION IS SUPPORTED BY THE RESTRICTION OF
SUCH FILMS IN THIS and OTHER DEEP SEA BASALTS TO
PARTLY OR WHOLLY GLASSY HOST ROCKS);
Phenocrysts: PLAGIOCLASE ( TO 1%)
Size(mm): <1
PLAG MICROPHENOCRYSTS (& POSSIBLY OLIVINE) PRESENT
IN BOTH THE GLASS and HYPO- TO HOLOCRYSTALLINE PARTS
OF THE PIECE;
OLIVINE
POSSIBLY OLIVINE MICROPHENOCRYSTS;
Groundmass : GLASS
Replacement: PALAGONITE
Minerals Replaced: GLASS
Leg : 34 Top/Bottom Interval(mm): 660/ 720 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.22
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.16
LITHOLOGY: PLAG MICROPHYRIC BASALT;
Piece No. : PCE 3A (68-72), 3B (66-72);
Texture : VERY FINE-GRAINED, MICROPHYRIC, VARIOLITIC;
Structure : THIN WHITE CALCITE PATCHES COAT JOINTS EXPOSED ON
TOP OF PIECES - THE MAIN JOINT SEPARATING THEM IS
LINED BY A VEIN OF CALCITE OR MONTMORILLONITE OR
BOTH - THE MONT IS RESINOUS and MAINLY DARK CHOCOLATE
BROWN BUT VARIES LOCALLY TO MEDIUM BROWN and DARK
GREEN, THE WALLS OF THE JOINT ARE ALTERED TO WAXY OR
DULL CLAY-RICH MATERIAL VARYING IN COLOR FROM RED-
BROWN TO YELLOW and ARE AT MOST 0.1MM THICK, THE
MONTMORILLONITE and CALCITE VEINS ARE 0.1-0.2MM THICK;
Alteration : FAIRLY FRESH
DESPITE THE CONCENTRATION ON ALTERATION IN THIS
DESCRIPTION THE CORE IS NOT HIGHLY ALTERED
COMPARED TO MOST DSDP AND DREDGED DEEP OCEAN
BASALTS SAMPLED AWAY FROM CRESTS OF SPREADING
RIDGES;
Comments : SHARPLY BOUNDED COLOR VARIANTS ARE DISTRIBUTED WITH
DARKER AREAS ADJACENT TO JOINTS, PCE 3B IS VERY DARK
YELLOWISH GRAY (5Y 2.5/1) IN A 3MM ZONE ADJACENT TO
THE MAIN JOINT SEPARATING A&B AND DARK YELLOWISH
GRAY (5Y 3/2) FARTHER AWAY, THE COLORS ON THE BOTTOM
OF PCE 3A ARE (5Y 2.5/1) AND (5Y 2.5/2) - ON THE TOP
SIDE OF 3A THEY ARE BLACK (2.5YR 2.5/0) AND DARK
YELLOWISH GRAY (5Y 3/1) - THESE COLOR DIFFERENCES
REFLECT DIFFUSION-CONTROLLED ALTERATION EMANATING
FROM JOINTS, THE MOST VISIBLE DIFFERENCES UNDER A
BINOCULAR MICROSCOPE ARE THE SECONDARY COLORS OF
MESOSTASIS--YELLOW TO BROWN IN LESS ALTERED ZONES
and DARKER BROWN TO RED IN DARKER MORE ALTERED ZONES;
Phenocrysts: PLAGIOCLASE ( TO 1%)
Size(mm): TO 0.5
MICROPHENOCRYSTS;
Replacement: MONTMORILLONITE
CALCITE
CALCITE CONFIRMED IN GRAIN MOUNT IN OIL - VERY
FINE-GRAINED HENCE THE OPAQUE WHITENESS OF THE
VEIN;
Leg : 34 Top/Bottom Interval(mm): 730/ 820 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.32
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.23
LITHOLOGY: PLAG MICROPHYRIC BASALT;
MASSIVE;
Piece No. : PCE 4 (73-82);
Texture : VERY FINE-GRAINED TO APHANITIC, MICROPHYRIC;
Structure : MASSIVE;
Alteration : FAIRLY FRESH;
Comments : ALMOST UNJOINTED EXCEPT FOR A DISCONTINUOUS JOINT IN
THE LOWER PART DIPPING 65 DEGREES and THE REMNANT OF
AN IRREGULAR and FLAT TO GENTLY-DIPPING JOINT ON THE
TOP SURFACE, THE DISCONTINUOUS JOINT IS PARTIALLY
COATED BY DEEP BROWN RESINOUS MONTMORILLONITE, THE
JOINT ON THE TOP IS STAINED YELLOW TO LIGHT TAN
(WITH SOME RED SPOTS) and IS PATCHILY COATED WITH DEEP
BROWN TO DEEP GREEN RESINOUS MONTMORILLONITE THAT
INDICATES THAT THE JOINT WAS FILLED BY A VEIN
ORIGINALLY, DESPITE THE PAUCITY OF VISIBLE JOINTS
THE COLOR DISTRIBUTION SUGGESTS THAT THE WHOLE PIECE
APPROXIMATES A SINGLE NATURAL JOINT BLOCK, A MEDIUM
YELLOWISH GRAY ROCK (5Y 3/1) IS ALMOST WHOLLY
SURROUNDED BY A DARK YELLOWISH OR BROWNISH GRAY ROCK
(2.5Y 2.5/0) - THE DARKER ROCK IS OF THE TYPE WHICH
(IN OTHER SPECIMENS) FORMS ADJACENT TO JOINTS
WHEREAS THE LIGHTER ROCK TENDS TO OCCUPY THE CORES
OF JOINT BLOCKS, THE CONTACT IS SHARP (DIFFUSION-
CONTROLLED) and COMMONLY MECHANICALLY TIGHT--HOWEVER
THE CONTACT LOCALLY TENDS TO PART, THE WALLS OF THE
"MINICORES" WITHIN THIS PIECE SHOW THIN SEAMS OF
DARK PENETRATING and ISOLATING LENSES OF LIGHTER ROCK:
THE SEAMS HAVE NO VISIBLE JOINT CONTROL and MAY
SENSITIVELY MARK INCIPIENT JOINTS THAT FACILITATED
FLOW OR DIFFUSION OF PORE FLUIDS - SIMILAR SEAMS ARE
COMMONLY SEEN IN DREDGED ROCKS WITH AN INTERMEDIATE
DEGREE OF ALTERATION;
Phenocrysts: PLAGIOCLASE ( <1%)
Size(mm): TO 0.5
MICROPHENOCRYSTS;
OLIVINE
POSSIBLY MICROPHENOCRYSTS OF OLIVINE;
Replacement: MONTMORILLONITE
Leg : 34 Top/Bottom Interval(mm): 830/ 910 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.41
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.33
LITHOLOGY: PLAG MICROPHYRIC BASALT;
SIMILAR TO PCE 4;
Piece No. : PCE 5 (83-91);
Texture : VERY FINE-GRAINED, MICROPHYRIC;
Structure : CONTAINS CALCITE VEINS;
Comments : LIKE PCE 4 THIS ONE APPROXIMATES A NATURAL JOINT
BLOCK IN WHICH A LIGHTER CORE (MEDIUM TO DARK
YELLOWISH GRAY (5Y 3/2)) IS ALMOST WHOLLY ENCLOSED
BY VERY DARK YELLOWISH GRAY (5Y 2.5/1) ROCK 5-10MM
THICK, CALCITE VEIN ON BOTTOM SURFACE (RELATIVELY
FLAT-LYING) and LIGHT BROWN FE.OXIDE STAINS ON TWO
SIDES OUTLINE PART OF THE ORIGINAL ANGULAR TO
SUBANGULAR JOINT BLOCK WITHIN WHICH DIFFUSION-
CONTROLLED ALTERATION HAS LEFT A DISTINCTLY ROUNDED
CORE - IF CARRIED TO THE EXTREME THIS WOULD PRODUCE
ONION-SKIN EXFOLIATION and RESIDUAL ROUNDED CORES
WHICH WHEN DREDGED FROM SEAMOUNTS COULD GIVE A FALSE
INDICATION FOR FORMER WAVE ABRASION and AN ERRONEOUS
CRITERION FOR WAVE PLANATION OF GUYOTS, THE CALCITE
VEINS ON THE BOTTOM SURFACE ARE WHITE and ABOUT 0.2MM
THICK and STAINED YELLOW TO LIGHT ORANGISH RED ALONG
THEIR WALLS - THE STAINED WALLS ARE DISTINCTLY
SPOTTED BY DARK MN.OXIDES WHICH LOCALLY ARE
DENDRITIC - IN A GRAIN MOUNT IN OIL THE VEINS ARE
VERY FINE-GRAINED CALCITE and MINOR ARAGONITE, PCE 5
IS AN EQUANT PIECE OF BASALT THAT MAY HAVE ROTATED
DURING DRILLING;
Vesicles : THE MAIN ROCK CONTAINS A TRACE AMOUNT OF MINUTE &
IRREGULAR VUGS WITH MINUTE PROJECTING CRYSTALS,
THE VUGS SHOW NO SPECIAL COATING OR ALTERATION &
PROBABLY REPRESENT DIKTYTAXITIC SPOTS WHICH FORMED
UPON LATE EXSOLUTION OF VAPORS BELOW THE CHILLED
CRUSTS OF COOLING UNITS (PILLOWS OR THIN FLOWS) -
COMMONLY BELOW ANY VESICLE-BEARING ZONE WHICH MAY
BE PRESENT;
Replacement: CALCITE
MANGANESE OXIDE
ARAGONITE
Leg : 34 Top/Bottom Interval(mm): 930/ 950 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.45
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.43
LITHOLOGY: MICROPHYRIC BASALT;
Piece No. : PCE 6 (93-95);
Texture : MICROPHYRIC;
Structure : A FLAT-LYING JOINT ON ONE PIECE IS PARTIALLY COATED
BY A LIGHT BROWN CALCITE VEIN 0.4MM THICK;
Alteration : MESOSTASIS (OLIVINE?) ALTERED TO YELLOW TO RED
MATERIAL, METAL STREAKS FROM THE BIT ON THE CORE
SURFACE ARE ALTERED TO BRIGHT RED RUST and IN SMALL
SPOTS RESEMBLES ALTERED MESOSTASIS;
Comments : CONTAINS TWO SMALL JOINT- and FRACTURE-BOUNDED PIECES;
Replacement: CALCITE
Leg : 34 Top/Bottom Interval(mm): 970/1030 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.53
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.47
LITHOLOGY: MICROPHYRIC BASALT;
Piece No. : PCE 7 (97-103);
Texture : VERY FINE-GRAINED, MICROPHYRIC;
Comments : PORTIONS OF TWO JOINT BLOCKS SEPARATED BY PROMINENT
VEIN, COLORS MUCH AS IN PCE 5, THIS and PCE 8 JOINTLY
FORM THE BEST-RECOVERED CORE IN 13-1 and SUGGEST THAT
THE BOUNDARIES BETWEEN BLOCKS WILL TEND TO BE
PRESERVED ONLY WHERE THE BIT IS CUTTING WITHOUT TOO
MUCH DISTURBANCE, WHERE THE ROCK IS DISTURBED DURING
CORING THE JOINTS WILL TEND TO OPEN and BE ABRADED -
DESTROYING ANY VEINS IN THEM and (IN CASES LIKE PCE 1
and POSSIBLY PCE 5) ALLOWING ROTATION OF THE CORE
FRAGMENTS - LEADING (AS IN PCE 1) TO SUBSPHERICAL
SPECIMENS, PATCHES OF WHITE CALCITE VEINS ON TOP
SURFACE (ABOUT 45-DEGREE DIP) and ON ONE VERTICAL
SURFACE + AN EXPOSED and FLAT-LYING DARK RED-STAINED
JOINT ON THE BOTTOM SURFACE BOTH INDICATE RELATIVELY
CLOSELY-SPACED JOINTS AND EXPLAIN THE ABUNDANCE OF
RELATIVELY DARK ALTERED ROCK, THE PATCHES OF WHITE
CALCITE VEINS ARE INTERLAYERED WITH DARK BROWN
RESINOUS SMECTITE WHICH GIVES A DARK APPEARANCE TO
THE JOINT SURFACE WHERE THE CALCITE HAS SPALLED OFF,
THE PROMINENT VERTICAL VEIN IS ZONED: NEAR THE TOP
IT IS THINNER and COLORED TAN SURROUNDED BY WHITE WITH
A RED STAIN ON THE SURFACE (SKETCH ON SHIPBOARD
FORM) - AT THE BOTTOM IT IS THICKER and COLORED TAN
SURROUNDED BY RED - THE CENTRAL TAN ZONE CONTAINS
SCATTERED MN.OXIDE SPOTS OR MICRONODULES UP TO 3MM
IN DIAMETER - IN OIL THE VEIN IS UNIFORMLY VERY
FINE-GRAINED and IS PROBABLY CALCITE, LOCALLY THE VEIN
ANASTOMOSES AND ENCLOSES LENSES OF BASALT -
INDICATING FILLING OF AN OPEN JOINT WHICH CONTAINED
LOOSE SPALLS OF WALL ROCK, THE MESOSTASIS OF THE
DARKER ROCK IS STAINED RED - MORESO NEAR THE THICK
VEIN;
Vesicles : Size(mm): TO 2 Percent:
DIKTYTAXITIC VUGS ARE MORE ABUNDANT and LARGER THAN
IN PCE 5, IN THE LIGHTER ROCK THE VUGS ARE
UNALTERED OR COATED BY A LIGHT BLUE FILM, IN THE
DARK MORE ALTERED ROCK THE WALLS ARE STAINED DARK
RED and THERE MAY LOCALLY BE A DARK RED DEPOSIT;
Replacement: CALCITE
SMECTITE
MANGANESE OXIDE
Leg : 34 Top/Bottom Interval(mm): 1040/1140 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.64
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.54
LITHOLOGY: MICROPHYRIC BASALT;
Piece No. : PCE 8 (104-114);
Texture : FINE-GRAINED, MICROPHYRIC, COARSER THAN ABOVE
PIECES;
Alteration : SLIGHTLY MORE ALTERED THAN ABOVE PIECES;
Comments : PCE 8 IS A SMALL PART OF A LARGE COMPOUND JOINT
BLOCK, VEINS ARE SEEN ON TOP SURFACE and ON SIDE NEAR
TOP, THE VEIN ON TOP IS WHITE CALCITE INTERLAMINATED
WITH DARK BROWN RESINOUS SMECTITE WITH VERY THIN
OUTER ZONES OF EARTHY RED-BROWN FE.OXIDE - WHERE THE
VEIN HAS SPALLED OFF THE WALL ROCK IS EITHER DARK
RED-BROWN (WHERE THE FE.OXIDE REMAINS) OR LIGHT
YELLOW-GREEN (CLAYEY FILM ON WALL ROCK) - THIS VEIN
IS IRREGULAR--VARYING FROM FLAT TO GENTLY DIPPING,
THE VEIN ON THE SIDE DIPS ABOUT 80 DEGREES and IS A
CONTINUATION OF THE PROMINENT VEIN IN PCE 7 BUT IS
LARGELY SPALLED OFF - IT IS EVIDENTLY SPALLED AT A
PLACE WHERE IT BRANCHED OR ANASTOMOSED (JUNCTION OF
3 JOINTS) AS INDICATED BY A RAISED RIDGE OF BASALT
WITH A PAPER-THIN VEIN ALONG ITS CENTER, THE ONLY
JOINTS PRESENT OTHER THAN THE TWO VEINS ARE SEAMS--
EITHER UNVEINED (1) OR LINED BY DARK BROWN RESINOUS
SMECTITE (2), NEITHER JOINT TRAVERSES THE WHOLE
ROCK, JOINT 1 IS INDEPENDENT OF THE DARK-LIGHT COLOR
BOUNDARY IN THE ROCK and JOINT 2 FOLLOWS THE BOUNDARY
LOCALLY and CROSS-CUTS IT ELSEWHERE, EITHER THE VEINS
FORMED LATE--AFTER MUCH OF THE ALTERATION HAD
OCCURRED--OR THE ALTERATION WAS CONTROLLED PRIMARILY
BY OTHER MUCH MORE OPEN JOINTS WHICH BOUNDED THE
BLOCK OF WHICH PCE 8 IS A PART - THUS JOINT 1 MAY
NEVER HAVE BEEN A PREFERRED CHANNEL OF FLUID
MOVEMENT and JOINT 2 IN A LIMITED WAY OR ONLY LATE IN
THE HISTORY OF THE ALTERATION PROCESS (OR VERY EARLY
BEFORE THE BROWNISH ALTERATION OF THE HOST ROCK),
THE SIZE and SHAPE OF THE PRIMARY JOINT BLOCK WAS SUCH
THAT THE DIFFUSION-CONTROLLED ALTERATION HAS
ISOLATED MORE THAN ONE ROUNDED and RESIDUAL &
RELATIVELY FRESH "CORE" - PARTS OF TWO OF WHICH ARE
VISIBLE IN PCE 8, FURTHER COMPLICATIONS OF THE
GEOMETRY OF ALTERATION IS SEEN ON THE WALLS OF
MINICORE G (SKETCH ON MICROFILMED VISUALS) WHERE THE
DARK ZONE SEPARATING THE TWO RELATIVELY FRESH AREAS
IS SEEN TO BE A COMPOUND BRANCHED SYSTEM OF DARK
ALTERED ROCK ENCLOSING LENSES OF RELATIVELY FRESH
ROCK - JOINT 2 FOLLOWS THE EDGE OF ONE OF THE DARK
SUBZONES, THE DARK ZONES ARE DARK YELLOWISH GRAY
(5Y 2.5/1) WITH MESOSTASIS (OLIVINE?) ALTERED TO
LIGHT YELLOW OR TAN - IF THE ALTERATION IS AFTER
OLIVINE THEN THIS ROCK MAY CONTAIN AN ACCUMULATION
OF OLIVINE AT THE BASE OF A COOLING UNIT, THE
LIGHTER and RELATIVELY FRESH ROCK IS MEDIUM YELLOWISH
GRAY (5Y 3/1), AT 107CM THE BROWN JOINT-CONTROLLED
STAIN CROSSCUTS A SMECTITE VEIN SO AS TO INDICATE
THAT THE VEIN IS EARLIER THAN and UNRELATED TO THE
LATER OXIDATIVE STAINING;
Vesicles : DIKTYTAXITIC VUGS ARE UNCOMMON and SMALL and ARE MORE
COMMON AT THE TOP OF PCE 8 THAN AT THE BOTTOM;
Phenocrysts: OTHER ( 1%)
Size(mm): TO 0.5
MICROPHENOCRYSTS;
Replacement: SMECTITE
CALCITE
FERROUS OXIDE
Leg : 34 Top/Bottom Interval(mm): 1160/1260 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.76
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.66
LITHOLOGY: MICROPHYRIC BASALT;
Piece No. : PCE 9 (116-126);
Texture : VERY FINE-GRAINED TO APHANITIC, MICROPHYRIC, THE
LOWER ENDS OF PCES E&F ARE RELATIVELY CHILLED;
Comments : COLOR IS DARK GRAY, CONSISTS OF 6 LOOSE SCRAMBLED
PIECES LABELED A-F and REFITTED BY SHAPE and VEINS, BY
COMPARISON WITH PCES 8&11 IT IS CONCLUDED THAT PCE 9
IS THE BASE OF THE COOLING UNIT OF WHICH PCES 3-8
ARE PARTS, THE GLASS SELVAGE IS MISSING BUT PROBABLY
LAY 5CM OR LESS BELOW PCE 9, DURING DRILLING PCE 9
MUST HAVE BEEN CORED WITHOUT DISRUPTION - WHEN IT
DID BREAK UP THE PIECES WERE CHIPPED BUT NOT ROUNDED
SO EVIDENTLY THE BREAK-UP HAPPENED LATE and UNDER SUCH
CIRCUMSTANCES THAT THE FRAGMENTS COULD TUMBLE FREELY
WITHOUT SEVERE ABRASION OR ROUNDING, THE DISRUPTION-
EXCEPT FOR THE SPALLING ALONG CORNERS and EDGES-WAS
ENTIRELY CONTROLLED BY VEINS and JOINTS - THE TWO MOST
PROMINENT ARE VERTICAL: ONE (EXPOSED ON FRAGMENTS A&
C-F) IS A RED TO YELLOW TO TAN TO YELLOW-GREEN
STAINED JOINT - ON F IT IS COATED BY A 3MM-THICK
LIGHT RED CALCITE VEIN ENCLOSING LENTICULAR SPALLS
OF BASALT--MUCH LIKE THE PROMINENT VEINS IN PCES 7&8
and PERHAPS A CONTINUATION OF THEM, THE SECOND
VERTICAL JOINT IS THE BOUNDARY BETWEEN A&C ON ONE
SIDE and B&D ON THE OTHER - IN PCE F IT CONTINUES AS A
JOINT WITH A CALCITE VEIN ABOUT 0.3MM THICK (LOCALLY
EXPANDS TO AT LEAST 0.8MM), THE JOINT SEPARATING E&F
IS PARTLY COLORED BY ORANGE and OCHRA and BROWN and WHITE
SURFACE STAINES IN A ZONED PATTERN BUT THERE IS NO
VEIN - THIS JOINT DIES OUT UPWARD IN C AS A HAIRLINE
CRACK--OTHER DARK BROWN TO RED STAINED JOINTS OF THE
SAME SET ARE DISCONTINUOUSLY EXPOSED ON THE SIDES OF
C&D&F, THE HORIZONTAL TO GENTLY DIPPING JOINTS ARE
STAINED DARK BROWN TO LIGHT YELLOW AND ARE PATCHILY
COATED BY FILMS OF CALCITE and DARK BROWN
MONTMORILLONITE, NEARNESS TO THE CHILLED EDGE OF A
FLOW UNIT IS INDICATED BY THE FINENESS OF GRAIN SIZE
IN LOWER PART OF E&F and BY THE INCREASED FREQUENCY &
CLOSENESS OF SPACING OF JOINTS and VEINS and BY THE
PRESENCE OF VITREOUS YELLOW and DARK RED PALAGONITE(?)
IN THE 3MM VEIN ON THE SIDE OF F SHOWN IN THE SKETCH
(SOURCE OF PALAG UNKNOWN), ORIENTATION OF PCE 9 IS
DICTATED BY LITHOLOGIC COMPARISON WITH PCES 8&11 AS
STATED ABOVE, BECAUSE OF THE CLOSE SPACING OF JOINTS
ALMOST ALL OF PCE 9 IS THE DARK ALTERED TYPE OF ROCK
SEEN ADJACENT TO JOINTS IN THE HIGHER PIECES IN
SEC 1 - HOWEVER COLOR ZONES ARE SEEN IN PART F WHEN
SAWED OPEN, ONLY IN PCE 9 WERE THE BOUNDING JOINTS &
VEINS EXTENSIVELY PRESERVED - THE VARIOUS BLOCKS IN
PCE 9 HAD PARTED BUT CORING CEASED BEFORE THE
BOUNDARIES WERE ABRADED BEYOND RECOGNITION;
Phenocrysts: OTHER ( <1%)
Size(mm): TO 0.5
MICROPHENOCRYSTS;
Replacement: PALAGONITE
MONTMORILLONITE
CALCITE
Leg : 34 Top/Bottom Interval(mm): 1250/1310 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.81
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.75
LITHOLOGY: BASALT;
Piece No. : PCE 10 (125-131);
Comments : SMALL FRAGMENTS (MAXIMUM SIZE 2.5CM) WHICH COULD
NOT BE FITTED TO OTHER PIECES;
Leg : 34 Top/Bottom Interval(mm): 1330/1480 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 112.98
Core: 13 Top of Core Depth (m) : 111.50
Sect: 1 Top of Section Depth(m): 112.83
LITHOLOGY: BASALT;
MASSIVE
Piece No. : PCE 11 (133-148);
Texture : FINE-GRAINED, ALMOST APHYRIC;
Structure : MASSIVE, UNJOINTED, CARBONATE VEINS;
Comments : WHITE TO LIGHT GRAY CARBONATE VEINS 0.1MM THICK ON
TOP (WITH A 45-DEGREE DIP) AND ON FLAT BOTTOM
SURFACE - THESE VEINS PRESUMABLY MARK PARTS OF THE
ORIGINAL JOINT BOUNDARIES OF THE BLOCK FROM WHICH
PCE 11 WAS CORED, DARK YELLOWISH GRAY (5Y 3/2) &
MEDIUM GRAY (2.5Y 4/0) PORTIONS--THE DARKER and MORE
ALTERED PART HAS RED ALTERED MESOSTASIS OR OLIVINE,
BOTTOM CARBONATE VEIN IN OILS IS CALCITE &
ARAGONITE;
Replacement: CARBONATE
CALCITE
ARAGONITE
Leg : 34 Top/Bottom Interval(mm): 0/ 70 Analyst: Bass, M.
Hole: 319 Sample Midpoint (m) : 114.57
Core: 14 Top of Core Depth (m) : 114.50
Sect: CC Top of Section Depth(m): 114.60
LITHOLOGY: APHYRIC BASALT;
Piece No. : PCE NO PIECE NUMBERS ASSIGNED;
Texture : MEDIUM TO COARSE-GRAINED, APHYRIC;
Structure : LARGELY MASSIVE and UNJOINTED INTERNALLY;
Alteration : FRESH TO ALTERED;
Comments : CONTAINS ONE LARGE (6.5CM) and TWO SMALL IRREGULAR
PIECES--ALL UNORIENTED, THE LARGE PIECE WAS STUCK
SIDEWAYS IN MOUTH OF CORE BARREL and VARIES FROM FRESH
and DARK GRAY TO ALTERED and DARK BROWNISH GRAY - THE
TWO SMALL PIECES ARE THE SAME EXCEPT ARE ENTIRELY
ALTERED, THE LARGE PIECE HAS ONE VERTICAL GREEN
SMECTITE VEIN WITH AN IRREGULAR BUT POLISHED SURFACE
AS IF IT MIGHT HAVE MOVED SLIGHTLY - THE PIECE IS
OTHERWISE UNJOINTED and UNVEINED, REMNANTS OF
IRREGULAR and GENTLY TO MODERATELY DIPPING JOINTS ON
ITS SURFACE ARE COATED BY THIN DISCONTINUOUS FILMS
OF BROWN and YELLOWISH GREEN and GREEN and LIGHT BLUE-
GREEN SMECTITE, THE SMALL PIECES ARE UNVEINED;
Vesicles :
Location: Filling: SMECTITE
Shape : IRREGULAR
ONE OF THE SMALL PIECES HAS AN IRREGULAR 1.5X0.5MM
AMYGDULE ZONED INWARDLY FROM LIGHT BROWN TO
GREENISH WHITE TO DARK GREEN TO YELLOW SMECTITE
WITH A TINY RESIDUAL HOLE;
Replacement: SMECTITE
Minerals Replaced: OLIVINE
IN THE FRESH ROCK OLIVINE MESOSTASIS ARE ALTERED
TO LIGHT BLUE-GREEN SMECTITE - IN THE ALTERED ROCK
TO RED-BROWN SMECTITE;
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