Leg : 60 Top/Bottom Interval(mm): 170/ 180 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 36.50 Rock Type: TUFF
Core: 5 Sample Midpoint(m) : 36.68 Sect/Pc #: 1/
ROCK = VITRIC TUFF
ALTERED XTL-LITHIC VITRIC TUFF;
Where sampled: PEBBLE IN SEDIMENT*
Phenocrysts- PLAGIOCLASE ( 5%)
Size(mm): 0.1-0.4 Morphology: ANGULAR
CRYSTALS-NOT PHENOS;
CLINOPYROXENE ( 3%)
Size(mm): 0.1-0.4 Morphology: ANGULAR
GREENISH,CRYSTALS-NOT PHENOS;
QUARTZ ( 1%)
CRYSTALS-NOT PHENOS;
OTHER ( 10%)
LITHIC FRAGMENTS,INCLUDES PLAG-CPX HYALOPILITIC
BASALT FRAGMENTS*
Groundmass - GLASS
GLASSY MATRIX ALTERED TO CLAYS,SOME VITRIC GRAINS
ALTERED TO PALAGONITE(PRIOR TO INCORPORATION)*
Alteration - CLAY MINERALS
Replacing: GLASS,PALAGONITE
FERROUS OXIDE
Location: PERVASIVE
RED COLOR*
Leg : 60 Top/Bottom Interval(mm): 240/ 250 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 36.50 Rock Type: TUFF
Core: 5 Sample Midpoint(m) : 36.75 Sect/Pc #: 1/
ROCK = VITRIC TUFF
ALTERED XTL-VITRIC TUFF*
Groundmass - GLASS
MOST OF ROCK,ALTERED TO CLAYS + FE-OXIDES;
COMBINATION ( 10%)
Size(mm): 0.05-0.15
INCLUDES ANGULAR FRAGMENTS OF PLAG + CPX + QUARTZ*
Alteration - CLAY MINERALS
Replacing: GLASS
FERROUS OXIDE
Replacing: GLASS
RED COLOR*
Leg : 60 Top/Bottom Interval(mm): 120/ 130 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 55.50 Rock Type: IGNEOUS
Core: 7 Sample Midpoint(m) : 57.72 Sect/Pc #: CC/PCE 1
ROCK = APHYRIC BASALT
ALTERED;
Texture: HYALOPILITIC,SPHERULITIC;
Where sampled: COBBLE IN SEDIMENTS*
Groundmass - GLASS ( 45%)
DEVITRIFIED,NOW ALTERED TO RED-ORANGE CLAYS;
PLAGIOCLASE ( 15%)
Size(mm): 0.1-0.5 Morphology: ACICULAR
MICROLITES AND SOME INTERSTITIAL;
MAGNETITE ( 1-2%)
Size(mm): TO 0.03 Morphology: SKELETAL
ABUNDANT SKELETAL CRYSTALLITES AND MORE LARGE
IRREGULAR GRAINS UP TO 0.03 MM*
Alteration - CLAY MINERALS ( 40%)
Location: GENERAL Replacing: GLASS
CLEAR COLOR*
Vesicles -
Size(mm): 1.0-5.0
Percent: 5
Location: ONE SIDE OF
Filling: NONE
Shape: SUB-ROUNDED
Location: SECTION
ONLY A FEW ARE PRESENT BUT THEY ARE LARGE*
Leg : 60 Top/Bottom Interval(mm): 120/ 131 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 55.50 Rock Type: IGNEOUS
Core: 7 Sample Midpoint(m) : 57.72 Sect/Pc #: CC/PCE 2
ROCK = PLAGIOCLASE SPARSELY PHYRIC BASALT
ALTERED;
Texture: HYALOPILITIC;
Where sampled: COBBLE IN SEDIMENTS*
Phenocrysts- PLAGIOCLASE ( TR%)
Size(mm): 0.1-0.2 Morphology: TABULAR
Groundmass - GLASS ( 40%)
NOW ALTERED TO CLAYS + REDDISH AMORPHOUS MATERIAL
(ONCE WAS SPHERULITIC CPX);
PLAGIOCLASE ( 10%)
Size(mm): 0.01-0.1 Morphology: ACICULAR NEEDLES
CLINOPYROXENE ( TR%)
TINY XTLS-MANY ALTERED TO CLAYS*
Alteration - CLAY MINERALS ( 45%)
Location: MOST PLACES Replacing: GLASS,CPX
FERROUS OXIDE ( 5%)
Replacing: GLASS,CPX
RED COLOR,CLAY + FE.OX REPLACE SOME CPX*
Vesicles -
Percent: 5
Leg : 60 Top/Bottom Interval(mm): 350/ 370 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 65.00 Rock Type: IGNEOUS
Core: 8 Sample Midpoint(m) : 65.36 Sect/Pc #: CC/
ROCK = ALTERED HYALOCLASTITE;
Where sampled: AT CONTACT WITH SEDIMENTS
UNCONFORMITY(?)*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 0.1X0.4 Morphology: TABULAR
CLINOPYROXENE ( TR%)
Size(mm): 1.0-1.5
Groundmass - GLASS ( 84%)
ANGULAR GREEN ALTERED GLASS FRAGMENTS UP TO 5.0MM
IN DIAMETER IN CRUSHED GLASS MATRIX,GREEN GLASS
ALTERATION IS A FAINTLY BIREFRINGENT MATERIAL;
CLINOPYROXENE ( 10%)
Size(mm): 0.01-0.1 Morphology: ACICULAR
MICROLITES IN ALTERED GLASS;
PLAGIOCLASE ( 5%)
Size(mm): 0.1-0.2 Morphology: ACICULAR
MICROLITES IN ALTERED GLASS*
Alteration - CLAY MINERALS
Location: THROUGHOUT Replacing: GLASS
ZEOLITE ( 1-2%)
10% CEMENTING MASS WITH CLAY,BETWEEN ALTERED GLASS
FRAGMENTS;
FERROUS OXIDE
Location: SCATTERED Replacing: GLASS
RED COLOR*
Vesicles -
Size(mm): 0.2-0.4
Percent: 2
Location: GLASS FRAGS
Filling: ZEOLITES,CLAYS
Shape: ROUND
Leg : 60 Top/Bottom Interval(mm): 60/ 80 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 74.50 Rock Type: IGNEOUS
Core: 9 Sample Midpoint(m) : 74.57 Sect/Pc #: CC/
ROCK = PLAGIOCLASE SPARSELY PHYRIC BASALT
ALTERED,TALUS(?);
Texture: HYALOPILITIC*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 0.1X0.4
GROUPED AS GLOMEROCRYSTS*
Groundmass - GLASS ( 50%)
ONCE SPHERULITIC,NOW ALTERED TO CLAYS + FE-OXIDES;
PLAGIOCLASE ( 15%)
Size(mm): 0.01X0.4 Morphology: ACICULAR
ALSO HAVE SMALLER GRAINS OF 0.01X0.2MM;
MAGNETITE ( 1%)
Size(mm): 0.01-0.05 Morphology: CUBIC,SKELETAL
Alteration - CLAY MINERALS ( 30%)
Replacing: GLASS
PALE GREEN COLOR*
Vesicles -
Size(mm): 0.1-0.3
Percent: 3
Location: SCATTERED
Filling: NONE
Shape: IRREGULAR-
Shape: ROUND
Leg : 60 Top/Bottom Interval(mm): 120/ 130 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 74.50 Rock Type: IGNEOUS
Core: 9 Sample Midpoint(m) : 74.63 Sect/Pc #: CC/
ROCK = PLAG-CPX SPARSELY PHYRIC BASALT;
Texture: HYALOPILITIC;
Where sampled: PILLOW INTERIOR
AREA UNCERTAIN*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 0.5-0.7
APPROX COMP AN55;
CLINOPYROXENE ( TR%)
Groundmass - GLASS ( 72%)
MESOSTASIS-PARTIALLY ALTERED,CRYPTOCRSTALLINE-WITH
SPHERULITIC CPX(?)+FE.OX PARTLY ALTERED TO CLAY;
PLAGIOCLASE ( 20%)
Size(mm): 0.05-0.1 Morphology: ACICULAR-SKELETAL
CLINOPYROXENE ( 1-2%)
OBSCURE IN MESOSTASIS;
MAGNETITE ( 1%)
Size(mm): 0.001-0.02 Morphology: CUBIC,BLOCKY
TWO TYPES-BRANCHING AND TRELLICED IN MESOSTASIS,
CUBIC AND BLOCKY ELSEWHERE*
Alteration - CLAY MINERALS
Location: LINE VESICLES Replacing: GLASS,FE.OXIDES
VERY DISPERSED,FE.OX PARTLY ALTERED TO GREEN CLAYS
(MAYBE SOME BROWN CLAYS)*
Vesicles -
Size(mm): 0.1-1.0
Percent: 5
Location: SCATTERED
Filling: NONE
Shape: ROUND
FINER GRAINED NEXT TO VESICLES MORE SPHERULITIC*
Leg : 60 Top/Bottom Interval(mm): 250/ 270 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 84.00 Rock Type: UNIDENTIFIED
Core: 10 Sample Midpoint(m) : 84.26 Sect/Pc #: CC/
ROCK = QUARTZ-CEMENTED BASALT BRECCIA
IN PLACE(?) TALUS(?),THIN SECTION CONSISTS OF ONE
LARGE BASALTIC FRAGMENT + SEVERAL SMALLER ONES;
Texture: SPHERULITIC
FORMERLY SPHERULITIC IN BASALT FRAGMENTS*
Groundmass - MICROCRYST GROUNDMASS ( 95%)
INCLUDES ALTERED DEVITRIFIED GLASS AND ABUNDANT
CLAY PSEUDOMORPHS AFTER SPHERULITIC CPX;
QUARTZ ( 40%)
Size(mm): 0.01-0.02
ENCASES BASALT FRAGMENTS AS A CRYSTALLINE QUARTZ
CEMENT,ALSO REPLACES BASALT FRAGMENTS;
PLAGIOCLASE ( 5%)
Size(mm): 0.01-0.02 Morphology: ACICULAR NEEDLES
PYRITE ( 3%)
CONTAINED WITHIN THE QUARTZ VEINS;
MAGNETITE ( TR%)
Morphology: SKELETAL
ONE OR TWO LARGE SKELETAL FRAGMENTS*
Alteration - QUARTZ ( 40%)
Location: VEINS, Replacing: GLASS
Location: GROUNDMASS
FORMS XTLS IN VEINS(0.05 IN DIAMETER),ALSO PRESENT
AS A SECONDARY MINERAL IN BASALT GROUNDMASS;
PYRITE ( 3%)
ASSOCIATED WITH QUARTZ VEINS*
CLAY MINERALS
Replacing: CPX,GLASS
Vesicles -
Percent: 0
Leg : 60 Top/Bottom Interval(mm): 250/ 260 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 93.50 Rock Type: IGNEOUS
Core: 11 Sample Midpoint(m) : 93.76 Sect/Pc #: 1/PCE 5
ROCK = PLAG-CPX SPARSELY PHYRIC BASALT;
Texture: HYALOPILITIC,GLASSY,SPARSELY PHYRIC;
Where sampled: NEXT TO GLASSY MARGIN
PEBBLE AMONG METABASALTS RECOVERED IN TALUS OR
BRECCIA*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 0.1-0.4 Morphology: TABULAR
APPROX COMP AN50-55,SOME WITH ANOMALOUSLY LOW 2VZ-
OF ABOUT 30,LABRADORITE;
CLINOPYROXENE ( 1%)
Size(mm): 0.3-0.8
2VX OF 80,PALE GREEN AND FAINTLY PLEOCHROIC*
Groundmass - PLAGIOCLASE ( 15%)
Size(mm): 0.1-0.4 Morphology: ACICULAR-SKELETAL
ENCLOSES GLASS,SOME PLAG PHANTOMS-XTL OUTLINES
PRESENT BUT ONLY COLOR OF GLASS IN PLANE LIGHT;
CLINOPYROXENE ( 5%)
Size(mm): 0.01-0.1 Morphology: ACICULAR
MAGNETITE ( TR%)
Size(mm): TO 0.01 Morphology: CUBIC
GLASS
TWO TYPES-ONE HAS RICH RED-BROWN COLOR AND
SURROUNDS GROUNDMASS XTLS AND THE OTHER IS PALE
YELLOW AND SURROUNDS VESICLES,SECOND TYPE IS
PERHAPS A KIND OF PALAGONITE(?)*
Alteration - CLAY MINERALS
IN YELLOW GLASS NEAR VESICLES,FAINTLY
BIREFRINGENT*
Vesicles -
Size(mm): 0.1-0.5
Percent: 5
Location: SCATTERED
Filling: NONE
Shape: ROUND TO
Shape: IRREGULAR
SURROUNDED WITH GLASS*
Leg : 60 Top/Bottom Interval(mm): 290/ 310 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 93.50 Rock Type: METAMORPHIC
Core: 11 Sample Midpoint(m) : 93.80 Sect/Pc #: 1/PCE 6
ROCK = QUARTZ-AMPHIBOLE-PLAGIOCLASE METABASALT;
Texture: GRANO-POIKILOBLASTIC
PRIOR SUBOPHITIC TEXTURES*
Groundmass - AMPHIBOLE ( 50%)
AFTER CPX,YELLOWISH-GREEN AND FAINTLY PLEOCHROIC;
PLAGIOCLASE ( 38%)
Morphology: RELICT
MUCH IS RELICT FROM PRIOR SUBOPHITIC TEXTURES;
QUARTZ ( 10%)
IN PATCHES BETWEEN THE FELDSPARS AND AMPHIBOLES;
CLINOPYROXENE ( 1%)
Morphology: RELICT
TRACES OF RELICT CPX IN THE AMPHIBOLE;
MAGNETITE ( 1%)
Size(mm): 0.01-0.04 Morphology: SKELETAL,CUBIC
MANY QUARTZ-ALBITE(?) INTERGROWTHS*
Alteration - AMPHIBOLE ( 50%)
Replacing: CPX
GREEN,SOME FAINTLY PLEOCHROIC;
QUARTZ ( 10%)
Leg : 60 Top/Bottom Interval(mm): 0/ 0 Describer: Natland, J.
Hole: 460A Top of Core Depth(m) : 99.50 Rock Type: METAMORPHIC
Core: C 1 Sample Midpoint(m) : 99.50 Sect/Pc #: /
ROCK = QUARTZ-AMPHIBOLE-PLAGIOCLASE METABASALT
THE ROCK IS A SILICIFIED BASALT,UPPER GREENSHIST
LOWER AMPHIBOLE FACIES;
Texture: GRANO-POIKILOBLASTIC
SOME PRIOR SUBOPHITIC TEXTURES*
Phenocrysts- CLINOPYROXENE ( TR%)
Size(mm): TO 0.2 Morphology: RELICT,GRANULAR
Groundmass - AMPHIBOLE ( 60%)
AFTER GLASS AND CPX;
PLAGIOCLASE ( 32%)
Size(mm): 0.1-0.5 Morphology: ACICULAR,RELICT
MUCH IS RELICT FROM PRIOR SUBOPHITIC TEXTURES;
QUARTZ ( 7%)
QUARTZ XTLS PERMEATE THE GROUNDMASS AND FILL OR
PARTLY FILL SOME VESICLES,AFTER GLASS;
CLINOPYROXENE ( TR%)
Morphology: RELICT
SURROUNDED BY AMPH,ALTERED TO CLAYS;
GLASS
ALTERED TO CLAYS+QUARTZ+AMPH*
Alteration - AMPHIBOLE ( 60%)
Replacing: GLASS,CPX
QUARTZ ( 7%)
Location: THROUGHOUT Replacing: FILL VESICLES,GLASS
CARBONATE ( 1%)
Location: IN VESICLES
Vesicles -
Percent: 0
VESICLES,IF THEY WERE PRESENT HAVE BEEN COMPLETELY
OBLITERATED BY METAMORPHISM*
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