Leg : 60 Top/Bottom Interval(mm): 120/ 150 Describer: Meijer, A.
Hole: 460 Top of Core Depth(m) : 57.00 Rock Type: IGNEOUS
Core: 7 Sample Midpoint(m) : 58.34 Sect/Pc #: CC/
ROCK = APHYRIC BASALT;
Texture: HYALOPILITIC-QUENCH;
Where sampled: NEXT TO GLASSY MARGIN*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): 0.2-0.5 Morphology: ACICULAR-TABULAR
APPROX COMP AN50-60;
CLINOPYROXENE ( TR%)
Size(mm): TO 0.2 Morphology: SUBHEDRAL
APPROX COMP UNCERTAIN,SOME CPX PHENOS PLUCKED OUT*
Groundmass - GLASS ( 48%)
DEVITRIFIED,FINE-GRAINED MASS OF CRYPTXLN CPX +
CLAY + GLASS;
CLINOPYROXENE ( 30%)
Size(mm): 0.01-0.05 Morphology: SPHERULITIC,EUHEDRAL
EUHEDRAL XTLS ARE RARE AND STUBBY,CPX PARTLY
ALTERED TO CLAY,APPROX COMP UNCERTAIN;
PLAGIOCLASE ( 20%)
Size(mm): 0.05-0.2 Morphology: ACICULAR
GENERALLY UNALTERED*
Alteration - CLAY MINERALS
Replacing: GLASS
Vesicles -
Size(mm): 0.1-0.2
Percent: 1
Location: GROUNDMASS
Filling: NONE
Shape: OVOID
COULD BE PLUCKED OUT PYROXENE*
Leg : 60 Top/Bottom Interval(mm): 120/ 150 Describer: Natland, J.
Hole: 460 Top of Core Depth(m) : 57.00 Rock Type: IGNEOUS
Core: 7 Sample Midpoint(m) : 58.34 Sect/Pc #: CC/
ROCK = APHYRIC BASALT
SPARSELY PLAG-CPX PHYRIC OR APHYRIC BASALT(FROM
ICD),TWO DESCRIPTIONS FOR THIS SECTION;
Texture: SPHERULITIC;
Where sampled: COBBLE IN SEDIMENTS*
Phenocrysts- PLAGIOCLASE ( TR%)
Size(mm): 0.1-0.2 Morphology: SKELETAL
CLINOPYROXENE ( TR%)
Size(mm): TO 0.1 Morphology: GRANULAR
Groundmass - MICROCRYST GROUNDMASS ( 95%)
INCLUDES CPX SPHERULITES + CLAYS OF ORANGE-BROWN
COLOR,MINOR FLOW PRODUCED GLASSY STREAKS OR
PARTING WITH DUST-LIKE OPAQUES;
Alteration - CLAY MINERALS ( 15%)
Replacing: GLASS
ALSO SOME CRACKS LINED WITH CLAYS*
Vesicles -
Percent: 0
Leg : 60 Top/Bottom Interval(mm): 1480/1500 Describer: Meijer, A.
Hole: 460 Top of Core Depth(m) : 66.50 Rock Type: IGNEOUS
Core: 8 Sample Midpoint(m) : 67.99 Sect/Pc #: 1/
ROCK = CPX PHYRIC BASALT
HIGH RESEMBLANCE TO BASALTS OF SITE 458,COULD ALSO
BE CALLED A HIGH MG ANDESITE;
Texture: HYALOPILITIC;
Where sampled: NEXT TO GLASSY MARGIN*
Phenocrysts- CLINOPYROXENE ( 5%)
Size(mm): 0.05-0.5 Morphology: EUHEDRAL,TABULAR,HOPPER
SIZE RANGE IS BIMODAL OF SIZES 0.2-0.5 + 0.05-0.1,
EUHEDRAL XTLS SHOW COMPLEX BLOCKY TWINNING,TABULAR
XTLS HAVE LOW EXTINCTION ANGLES*
Groundmass - GLASS ( 60%)
ALTERED TO CLAYS AND FE-OXIDES;
PLAGIOCLASE
OCCURS AS NEEDLE-LIKE XTLS IN SPHERULITIC SWORLS;
FERROUS OXIDE
GENERALLY ASSOCIATED WITH CPX MICROPHENOCRYSTS*
Alteration - CLAY MINERALS
Location: LINE VESICLES Replacing: GLASS
OXIDES
SOME OXIDATION EVIDENT*
Vesicles -
Size(mm): 0.01-0.5
Percent: 35
Location: THROUGHOUT
Filling: CLAY-LINED
Shape: IRREGULAR-
Shape: OVOID
Leg : 60 Top/Bottom Interval(mm): 1480/1500 Describer: Natland, J.
Hole: 460 Top of Core Depth(m) : 66.50 Rock Type: IGNEOUS
Core: 8 Sample Midpoint(m) : 67.99 Sect/Pc #: 1/
ROCK = CPX PHYRIC BASALT
ROCK RESEMBLES SOME BASALTS(CPX-RICH) OF SITE 458
(UNIT 3);
Texture: SPHERULITIC;
Where sampled: COBBLE IN SEDIMENTS*
Phenocrysts- CLINOPYROXENE ( 1%)
Groundmass - CLINOPYROXENE ( 5%)
Size(mm): 0.1-0.3 Morphology: ACICULAR,DENDRITIC
PLAGIOCLASE
SPHERULITIC AND ABUNDANT;
MICROCRYST GROUNDMASS
ALTERED TO ORANGE FE-OXIDES(CLAYS?),PLAG AND
MICROXLN VERY INTIMATELY INTERGROWN,ESTIMATES OF
PROPORTIONS DIFFICULT TO MAKE-PERHAPS 50-50(?)*
Alteration - CLAY MINERALS ( 15%)
Replacing: GLASS
THIN CLEAR LINING ON VESICLES,IN BETWEEN CPX
SPHERULITES*
Vesicles -
Size(mm): 0.1-0.3
Percent: 20
Location: UBIQUITOUS
Filling: CLAY-LINED
Shape: IRREGULAR
Leg : 60 Top/Bottom Interval(mm): 740/ 760 Describer: Meijer, A.
Hole: 460 Top of Core Depth(m) : 76.00 Rock Type: IGNEOUS
Core: 9 Sample Midpoint(m) : 76.75 Sect/Pc #: CC/
ROCK = CPX-PLAG SPARSELY PHYRIC BASALT;
Texture: INTERSERTAL;
Where sampled: PILLOW INTERIOR
AREA UNCERTAIN*
Phenocrysts- CLINOPYROXENE ( 2%)
Size(mm): 0.2-0.6 Morphology: EUHEDRAL-TABULAR
PLAGIOCLASE ( 1%)
Size(mm): 0.2-0.5 Morphology: SUBHEDRAL-ANHEDRAL
APPROX COMP AN65;
OLIVINE ( 1%)
ONLY IDDINGSITE RIMS REMAIN;
ORTHOPYROXENE ( TR%)
IDENTITY UNCERTAIN*
Groundmass - GLASS ( 32%)
DEVITRIFIED AND ALTERED TO CLAYS;
PLAGIOCLASE ( 20%)
Size(mm): 0.05-0.2 Morphology: SPHERULITIC-TABULAR,HOPPER
SPHERULITIC XTLS HAVE COMPLEX ZONING;
CLINOPYROXENE ( 10%)
Size(mm): 0.05-0.2 Morphology: SKELETAL,SPHERULITIC
MAGNETITE ( 1%)
Size(mm): 0.01-0.02
Vesicles -
Size(mm): 0.1-0.3
Percent: 35
Location: THROUGHOUT
Filling: CLAY-LINED
Shape: IRREGULAR-
Shape: OVOID
Leg : 60 Top/Bottom Interval(mm): 740/ 760 Describer: Natland, J.
Hole: 460 Top of Core Depth(m) : 76.00 Rock Type: IGNEOUS
Core: 9 Sample Midpoint(m) : 76.75 Sect/Pc #: CC/
ROCK = PLAG-OL-CPX SPARSELY PHYRIC BASALT;
Texture: HYALOPILITIC-SPHERULITIC;
Where sampled: COBBLE IN SEDIMENTS
TALUS(?)*
Phenocrysts- PLAGIOCLASE ( 2%)
Size(mm): 0.1-0.7 Morphology: TABULAR-SKELETAL
FORMS GLOMEROCRYSTS;
OLIVINE ( 1%)
Size(mm): 0.1-0.4 Morphology: EUHEDRAL
ALTERED TO RED FE-OXIDES + CLAYS;
CLINOPYROXENE ( TR%)
Size(mm): 0.1-0.3
ORTHOPYROXENE ( TR%)
IDENTITY UNCERTAIN-ONLY ONE XTL*
Groundmass - MICROCRYST GROUNDMASS ( 45%)
ALTERED TO REDDISH OXIDES AND PERHAPS CLAYS;
CLINOPYROXENE ( 17%)
Morphology: SPHERULITIC
ABUNDANT SPHERULITIC;
PLAGIOCLASE ( 15%)
Size(mm): 0.1-0.5 Morphology: SKELETAL,ACICULAR
Alteration - CLAY MINERALS ( 10%)
Location: LINE VESICLES
MAY BE MORE DISPERSED*
Vesicles -
Size(mm): 0.1-0.5
Percent: 20
Location: GENERAL
Filling: CLAY-LINED
Shape: IRREGULAR
LARGER ONES HAVE ASSOCIATED GLASSY-SPHERULITIC
ZONES WITH ABUNDANT SMALLER VESICLES*
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