Leg : 28 Top/Bottom Interval(mm): 1170/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 168.00 Rock Type: IGNEOUS
Core: 11 Sample Midpoint(m) : 170.67 Sect/Pc #: 2/
ROCK = GABBRO
ALBITIZED,ALTERED;
Texture: COARSE-GRAINED
OCCURRENCE UNKNOWN,ROCK UNUSUALLY COARSE-GRAINED
AND APPARENTLY PLUTONIC OR HYPABYSSAL RATHER THAN
VOLCANIC,MAY BE PART OF A LARGE FOREIGN BOULDER,
BUT COULD BE AN ALTERED INTRUSIVE ASSOCIATED WITH
THE VOLCANIC FRAGMENTAL ROCKS,ALSO COULD BE A
PLAG-RICH XTL ACCUMULATE IN A FLOW ROCK,BUT
TEXTURES NOT INDICATIVE OF A CUMULATE ORIGIN*
Groundmass - PLAGIOCLASE ( 75%)
MOSTLY MEDIUM GRAINED BUT WITH A FEW COARSE GRAINS
(EXTINCTION ANGLE PERPENDICULAR TO A-AXIS = 25
DEGREES,APPROX COMP AN43),MOST MEDIUM GRAINED XTLS
ARE HIGHLY ALTERED-NOW ALBITE/OLIGOCLASE(I.R. >
1.54),STRONGLY SAUSSURITIZED*
Alteration - ALBITE
Replacing: PLAG
ALBITE/OLIGOCLASE;
FERROUS OXIDE
Replacing: MAFICS,OPAQUES
SECONDARY FE-OXIDES;
CHLORITE
Replacing: MAFICS,OPAQUES
BROWNISH MICACEOUS/CHLORITIC MATERIAL*
Leg : 28 Top/Bottom Interval(mm): 1400/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 168.00 Rock Type: IGNEOUS
Core: 11 Sample Midpoint(m) : 170.90 Sect/Pc #: 2/
ROCK = ANDESITIC VITROPHYRE
ALTERED;
Texture: SPARSELY PHYRIC,CRYPTOXTLLINE
NO ALBITIZATION OR FLOW TEXTURE*
Phenocrysts- PLAGIOCLASE ( 2%)
Size(mm): 1
APPROX COMP AN32,EXTINCTION ANGLE PERPENDICULAR TO
X-AXIS = 27,26 DEGREES*
Groundmass - FERROMAGNESIUM
LIGHT BROWN SEMI-OPAQUE;
OPAQUE MINERAL
Size(mm): .1-.3 Morphology: NEEDLES
SCATTERED,MORE OPAQUE THAN FE-MAGN;
ALTERED GLASS
Leg : 28 Top/Bottom Interval(mm): 1420/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 168.00 Rock Type: SEDIMENTARY
Core: 11 Sample Midpoint(m) : 170.92 Sect/Pc #: 2/
ROCK = BASALT CONGLOMERATE
CALCITE CEMENTED;
Texture: FINE-GRAINED,EQUIGRANULAR,INTERSERTAL*
Groundmass - ALTERED GLASS
Size(mm): 3-5
PEBBLES OF SEMI-OPAQUE HEMATITE ALTERED GLASS WITH
SCATTERED RANDOMLY ORIENTED MICROLITES OF VARYING
DENSITY;
BASALT
PEBBLE SEVERAL CM LONG OF ALTERED BASALT;
PLAGIOCLASE ( 60%)
SIMPLE ZONING COMMON,EXTINCTION ANGLE PERP. TO
X-AXIS = 19 DEGREES-APPROX COMP AN37,MAX.EXTINCT.
ANGLE 29-27DEG-APPROX COMP AN54;
FERROMAGNESIUM
CRYPTOXTLLINE,PEBBLES ENCLOSED IN A .1MM THICK
FILM OF CALCITE WHICH ALSO CEMENTS THE CONGLOM.,
MATRIX IS CLEAN COARSE SAND*
Alteration - CALCITE
Location: CEMENT
Leg : 28 Top/Bottom Interval(mm): 0/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 168.00 Rock Type: IGNEOUS
Core: 11 Sample Midpoint(m) : 171.10 Sect/Pc #: CC/
ROCK = BASALT
ALTERED, XTL-RICH;
Groundmass - PLAGIOCLASE ( 80%)
EXTINCTION ANGLE PERP. TO A-AXIS = 30 DEG.,APPROX
COMP AN60,2 GRAINS EXTINCT AT 35 DEG. WITH APPROX
COMP AN65, NORMAL ZONING TO APPROX AN40-50 COMMON
(LABRADORITE TO ANDESINE),UNUSUALLY FRESH(NON-
ALBITIZED);
Alteration - CHLORITE ( 20%)
Replacing: MAFICS
CHLORITE+FE-OXIDES*
Leg : 28 Top/Bottom Interval(mm): 1/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 187.00 Sect/Pc #: 1/
ROCK = ANDESITIC VITROPHYRE
ALTERED,SECTION 1;
Texture: GLASSY,VITROCLASTIC,PERLITIC*
Phenocrysts- PLAGIOCLASE ( 2%)
APPROX COMP AN30-35,R.I.>ALBITE,EXTINCTION ANGLE
PERP. TO X-AXIS = 17+16+13+13 DEGREES(4 DIFFERENT
MEASUREMENTS)*
Groundmass - GLASS
FERRO-BANDED GLASS SHOWING INCIPIENT
DEVITRIFICATION,WITH PATCHES OF PALE GREEN
CHLORITE,BANDING ENHANCED BY CRYPTOXTLLINE BROWN
FERRUGINOUS STUFF,GLASS AROUND PHENOS IS REALLY
HIGHLY DISTURBED AND DEFINES "PACKETS" OF GLASS
THAT WERE COHERENT IN A FLOWING GLASSY MEDIUM,ALSO
PATCHES OF GLASS FRAGMENTS-VITROCLASTIC,WELL
DEVELOPED CONCENTRIC LINES IN SETS,UP TO 1MM
ACROSS,PICKED OUT BY OPAQUE MATERIAL(PERLITIC
TEXTURES),SOME PERLITIC AREAS REPLACED BY QUARTZ
WITH DIAMETER APPROX .02MM ACROSS GENERALLY
FOLLOWING THE FRACTURE PATTERN BUT IN PLACES
CROSSING IT*
Alteration - CHLORITE
Replacing: GLASS
PALE GREEN,THIS IS SECTION 1*
Leg : 28 Top/Bottom Interval(mm): 2/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 187.00 Sect/Pc #: 1/
ROCK = PLAG SPARSELY PHYRIC BASALT
ALTERED,FINE-GRAINED,SECTION 2;
Texture: SPARSELY PHYRIC*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 1-3 Morphology: EUHEDRAL PRISMATIC
R.I.<ALBITE*
Groundmass - PLAGIOCLASE
Size(mm): .05-.2 Morphology: MICROLITES
ALTERED WITH SMALL PATCHES OF PALE GREEN CHLORITE
+SCATTERED SPECKS .05MM ACROSS OF HEMATITE*
Alteration - CHLORITE ( TR%)
Replacing: OL
EUHEDRAL-SUBHEDRAL,1MM LONG,BOWLINGITE?,PALE
GREEN*
Vesicles -
Size(mm): 1-4
Percent: .5
Location: PATCHES
Filling: CHALCEDONY
AMYGDULES OF CHALCEDONY WITH FINGERS EXTENDING
IN FROM THE MARGIN,THIS IS SECTION 2*
Leg : 28 Top/Bottom Interval(mm): 3/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 187.00 Sect/Pc #: 1/
ROCK = DACITIC VITROPHYRE
ALTERED,ALBITIZED,SECTION 4;
Texture: PHYRIC*
Phenocrysts- PLAGIOCLASE ( 10%)
PHENOS RESORBED AND ARE GLOMEROPHYRIC,APPROX COMP
ALBITE/OLIGOCLASE(R.I.=1.54)*
Groundmass - QUARTZ ( 5%)
GLASS ENTIRELY DEVITRIFIED TO QUARTZ+ALKALI
FELDSPAR,PROBABLY ALBITE,+CHLORITE+FE-OXIDES,ALL
IN HIGHLY IRREGULAR MASSES,RELICT PERLITIC(?)
STRUCTURES LOCALLY PRESENT*
Alteration - CHLORITE
Replacing: GLASS
FERROUS OXIDE
Replacing: GLASS
Leg : 28 Top/Bottom Interval(mm): 4/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 187.00 Sect/Pc #: 1/
ROCK = PLAG MODERATELY PHYRIC BASALT
ALTERED,ALBITIZED,SECTION 5;
Texture: MODERATELY PHYRIC,VESICULAR*
Phenocrysts- PLAGIOCLASE ( 5%)
Morphology: SUBHEDRAL
PATCHY ZONING,RARE CHLORITIC PSEUDOMORPHS AFTER
ORIGINAL MAFIC PHENOS*
Groundmass - PLAGIOCLASE
PLAG MICROLITE-BEARING CHLORITIC DENSE MATRIX THAT
MAY BE IN PART A DEVITRIFIED GLASS,PLAG APPEARS
TO BE ALBITE-OLIGOCLASE(I.R.>1.54);
QUARTZ
MINOR,MOSTLY IN FINE AGGREGATES THAT APPEAR TO
FILL VESICLES*
Alteration - CHLORITE
Location: VESICLES, Replacing: MAFICS
Location: MATRIX
CHALCEDONY
Location: VESICLES
CHALCEDONY/OPAL*
Vesicles -
Filling: CHLORITE,
Filling: CHALCEDONY
INTERLAYERED FILLING,SECTION 5*
Leg : 28 Top/Bottom Interval(mm): 5/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 187.01 Sect/Pc #: 1/
ROCK = ANDESITIC VITROPHYRE
SILICIFIED,SECTION 6;
Texture: MODERATELY PHYRIC,SPHERULITIC*
Phenocrysts- PLAGIOCLASE ( 5%)
Size(mm): 1-3
I.R.>ALBITE,EXTINCTION ANGLE PERP. TO 010 = 16DEG.
APPROX COMP AN32*
Groundmass - QUARTZ ( 70%)
Size(mm): .02-.05
OCCURS IN PLACES ORGANIZED AS SPHERULITES .2-.3MM;
PLAGIOCLASE ( 25%)
Size(mm): .02-.1 Morphology: LATHS
EXTINCTION ANGLE = 16 DEG.,APPROX COMP AN32;
OPAQUE MINERALS ( 2%)
Size(mm): .005
FILLING AREAS BETWEEN SPHERULITES OR AS SCATTERED
SPECKS-HEMATITE?,PHYRIC NATURE+SPHERULITES
INDICATE SILICIFICATION OF GLASS*
Leg : 28 Top/Bottom Interval(mm): 1/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.50 Sect/Pc #: CC/
ROCK = BASALT
ALTERED,SECTION 1;
Texture: FINE-GRAINED,INTERSERTAL*
Groundmass - PLAGIOCLASE ( 40%)
Size(mm): .05-.1 Morphology: MICROLITES+LATHS
I.R.>ALBITE,MAX.EXTINCTION ANGLE = 2DEG.,APPROX
COMP AN20(OLIGOCLASE);
ORTHOPYROXENE ( 20%)
ALTERED TO CHLORITE;
QUARTZ ( 35%)
Size(mm): .02
QUARTZ+ZEOLITE,ENCLOSED BY PLAG;
OPAQUE MINERALS
Morphology: EQUANT
INCLUDES HEMATITE*
Alteration - CHLORITE
Replacing: OPX
Vesicles -
Size(mm): .3
Filling: CHLORITE
QUARTZ LINED AMYGDULE SHOWING TWO GENERATIONS OF
CHLORITE FILLING*
Leg : 28 Top/Bottom Interval(mm): 2/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.50 Sect/Pc #: CC/
ROCK = BASALTIC VITROPHYRE
ALBITIZED,DEVITRIFIED,SECTION 2;
Texture: PHYRIC*
Phenocrysts- PLAGIOCLASE ( 20%)
Morphology: SUBHEDRAL
LITTLE ZONING-PATCHY TYPE IN ALTERED XTLS,EXTINCT.
ANGLE PERP. TO A-AXIS = 18DEG.,APPROX COMP AN35-
OTHERS ARE ALBITE-OLIGOCLASE ON BASIS OF I.R. =
1.54;
MAFIC ( 10%)
CHLORITIC PSEUDOMORPHS AFTER ORIGINAL MAFIC
MINERAL-CANNOT TELL PRIMARY MINERAL;
FERROUS OXIDE ( 5%)
SOME MAY BE PRIMARY BUT MOST APPEAR SECONDARY*
Groundmass - MATRIX
DEVITRIFIED GLASSY MATRIX,SUGGESTIONS OF PERLITIC
STRUCTURE LOCALLY PRESENT,ORIGINAL ROCK MAY HAVE
BEEN ANDESITIC BUT HERE TENTATIVELY INFERRED TO
HAVE BEEN BASALTIC-NEED CHEMICAL ANALYSIS*
Alteration - CHLORITE
Replacing: MAFICS
Leg : 28 Top/Bottom Interval(mm): 3/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.50 Sect/Pc #: CC/
ROCK = PLAG MODERATELY PHYRIC BASALT
ALBITIZED,SECTION 3;
Texture: MODERATELY PHYRIC,FINE-GRAINED,SPILITIC*
Phenocrysts- PLAGIOCLASE ( 5%)
Size(mm): 4
TWO TYPES-I.R.<ALBITE AND >ALBITE,EXTINCTION ANGLE
=31-40DEG.,APPROX COMP ALBITE-LABRADORITE-APPROX
HALF ARE ALBITE*
Groundmass - PLAGIOCLASE ( 30%)
Size(mm): .05-.1 Morphology: MICROLITES
MAX.EXT.ANGLE = 23DEG.,APPROX COMP AN50;
CLINOPYROXENE ( TR%)
MATRIX ( 60%)
DENSE CRYPTOXTLLINE GROUNDMASS BETWEEN MICROLITES,
MICROLITES AND PHENOS SHOW SOME FLOW ALIGNMENT*
Alteration - CHLORITE
Replacing: MAFICS
ELONGATE PRISMATIC REPLACE PYX,LOZENGE SHAPED
REPLACE OL*
Vesicles -
Percent: 0
Leg : 28 Top/Bottom Interval(mm): 4/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.50 Sect/Pc #: CC/
ROCK = BASALT
ALTERED,SECTION 4;
Texture: FINE-GRAINED,INTERSERTAL,EQUIGRANULAR*
Groundmass - PLAGIOCLASE
Size(mm): .02-.3 Morphology: LATHS
CLOUDY WITH PATCHY EXTINCTION,I.R.>ALBITE BUT MANY
MICROXTLLINE PATCHES WITH I.R.<ALBITE,ALBITE?;
QUARTZ ( 5%)
Size(mm): .1-.3
RELATIONSHIP TO OTHER GRAINS UNCLEAR*
Alteration - HEMATITE
Location: INTERSTITIAL
CHLORITE
Location: INTERSTITIAL
GREEN*
Leg : 28 Top/Bottom Interval(mm): 5/ 0 Describer: Barrett, P.J.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.51 Sect/Pc #: CC/
ROCK = ANDESITIC VOLCANIC GLASS VITROPHYRE
FERRUGINOUS ZEOLITIZED,SECTION 6;
Texture: FELTY*
Phenocrysts- PLAGIOCLASE ( 2%)
Size(mm): 1 Morphology: EQUANT EUHEDRAL+ROUNDED+
Morphology: ELONGATE
I.R.>ALBITE+ALSO<ALBITE,OLIGOCLASE*
Groundmass - OPAQUE MINERALS ( 98%)
Morphology: LATHS
SEMI-OPAQUE FERRUGINOUS GROUNDMASS I.R. SLIGHTLY
<ALBITE,ZEOLITE?,GROUNDMASS HAS FELTY TEXTURE
INDICATED BY OPAQUE LATHS RATHER THAN PLAG*
Alteration - CHLORITE ( TR%)
PASTEL GREEN*
Leg : 28 Top/Bottom Interval(mm): 6/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 187.00 Rock Type: IGNEOUS
Core: 13 Sample Midpoint(m) : 188.51 Sect/Pc #: CC/
ROCK = BASALT
ALTERED,ALBITIZED;SECTION 7;
Texture: SPILITIC,INTERGRANULAR*
Groundmass - PLAGIOCLASE ( 70%)
Morphology: LATHS
PATCHY ZONING,HIGHLY ALTERED AND ALBITIZED,FEW
SECONDARY CA MINERALS PRESENT + CALCITE AND
EPIDOTE,ROCK APPEARS TO HAVE BEEN ORIGINALLY
HOLOXTLLINE AND WITH INTERGRANULAR TEXTURE*
Alteration - OTHERS ( 30%)
Replacing: MAFICS
SECONDARY MAFICS-CHLORITE AND GREENISH-BROWN
MICACEOUS MINERAL(?)+FE-OXIDES(HEMATITE/GOETHITE,
LIMONITE,ETC.)*
Vesicles -
Filling: QUARTZ
QUARTZ LOCALLY CONCENTRATED IN WHAT APPEAR TO BE
VESICLE FILLINGS*
Leg : 28 Top/Bottom Interval(mm): 0/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 196.50 Rock Type: SEDIMENTARY
Core: 14 Sample Midpoint(m) : 196.60 Sect/Pc #: CC/
ROCK = VOLCANIC CONGLOMERATE
ALTERED;
Texture: TUFFACEOUS*
CONGLOMERATE COMPOSED OF PEBBLES/COBBLES OF MOSTLY
DEVITRIFIED VITROPHYRE IN AN ALTERED TUFFACEOUS
MATRIX CONTAINING ABUNDANT CARBONATE AND ALBITE
AND SEVERAL VARIOLITIC-LIKE MASSES OF CHLORITE*
Leg : 28 Top/Bottom Interval(mm): 0/ 0 Describer: Ford, A.
Hole: 264 Top of Core Depth(m) : 206.00 Rock Type: IGNEOUS
Core: 15 Sample Midpoint(m) : 206.10 Sect/Pc #: CC/
ROCK = SPILITIC BASALT
ALTERED;
Texture: FINE-GRAINED,HOLOXTLLINE,APHYRIC*
FINE LATHS OF PLAG,ALBITE AND OLIGOCLASE(I.R.>
CEMENT),INTERSTICES OF WHICH FILLED BY QUARTZ,
FE-OXIDES,CHLORITE AND EPIDOTE OR PUMPELLYITE,
GIVE A TEXTURE THAT APPEARS TO BE A RELICT
INTERGRANULAR TEXTURE.IN A FEW LARGER GRAINS THE
SODIC PLAG APPEARS TO HAVE REPLACED MORE CALCIC
ONES*
Vesicles -
Filling: QUARTZ,CHALC
Shape: SPHERULITIC
AMYGDULES OF QUARTZ AND CHALCEDONY*
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