Leg : 57 Top/Bottom Interval(mm): 450/ 500 Describer:
Hole: 439 Top of Core Depth(m) : 1096.50 Rock Type: IGNEOUS
Core: 32 Sample Midpoint(m) : 1098.48 Sect/Pc #: 2/
ROCK = DACITE;
Texture: HYALOOPHITIC-INTERSERTAL,
Where sampled: PEBBLE*
Phenocrysts- PLAGIOCLASE ( 8%)
Size(mm): TO 1.8X1.2 Morphology: EUHEDRAL-SUBHEDRAL
APPROX COMP AN40, HIGHLY ZONED;
CLINOPYROXENE ( TR%)
Size(mm): 0.34X0.08
COMPLETELY ALTERED;
BIOTITE ( TR%)
COMPLETELY ALTERED;
HORNBLENDE ( 5%)
Size(mm): 0.4X0.25
HIGHLY ALTERED;
KFELDSPAR ( 1%)
Size(mm): 0.8X0.5 Morphology: SUBHEDRAL-ANHEDRAL
PERTHITE*
Groundmass - PLAGIOCLASE ( 45%)
Size(mm): 0.17X0.03 Morphology: LATHS
APPROX COMP AN20;
MAGNETITE ( 4%)
Morphology: ANHEDRAL
VERY FINE GRAINED;
QUARTZ ( 7%)
Size(mm): 0.1X0.07 Morphology: ANHEDRAL
WITH CHALCEDONY;
ALKALI FELDSPAR ( 25%)
Size(mm): 0.17X0.05 Morphology: ANHEDRAL
Alteration - CHLORITE ( 5%)
Replacing: CPX,HBL,BIOTITE
CHALCEDONY
Leg : 57 Top/Bottom Interval(mm): 560/ 570 Describer:
Hole: 439 Top of Core Depth(m) : 1096.50 Rock Type: IGNEOUS
Core: 32 Sample Midpoint(m) : 1098.57 Sect/Pc #: 2/
ROCK = DACITE;
Texture: INTERSERTAL;
Where sampled: PEBBLE*
Phenocrysts- PLAGIOCLASE ( 5%)
Size(mm): 0.9X0.4 Morphology: EUHEDRAL-SUBHEDRAL
ZONED;
KFELDSPAR ( 2%)
Size(mm): 0.6X0.7 Morphology: ANHEDRAL
MAFICS ( 2%)
COMPLETELY ALTERED*
Groundmass - PLAGIOCLASE ( 40%)
Size(mm): 0.1X0.02 Morphology: LATHS
APPROX COMP AN20;
MAGNETITE ( 4%)
VERY FINE GRAINED;
QUARTZ ( 12%)
Size(mm): 0.06X0.09 Morphology: ANHEDRAL
ALKALI FELDSPAR ( 30%)
Morphology: ANHEDRAL
Alteration - CHALCEDONY ( 3%)
Location: GROUNDMASS
SPHERULITIC
CHLORITE ( 2%)
Location: PHENOCRYSTS Replacing: MAFICS
SPHERULITIC*
Leg : 57 Top/Bottom Interval(mm): 950/ 960 Describer:
Hole: 439 Top of Core Depth(m) : 1106.00 Rock Type: IGNEOUS
Core: 33 Sample Midpoint(m) : 1106.96 Sect/Pc #: 1/
ROCK = DACITE;
Texture: INTERSERTAL;
Where sampled: BOULDER*
Phenocrysts- PLAGIOCLASE ( 16%)
Size(mm): 2.35X1.65 Morphology: EUHEDRAL
APPROX COMP AN38,HIGHLY ZONED WITH INCLUSIONS,
SIZE GIVEN IS A MAXIMUM;
QUARTZ ( TR%)
Morphology: ANHEDRAL
MAFICS ( 8%)
Size(mm): TO 1.8X.41 Morphology: EUHEDRAL-ANHEDRAL
MAY HAVE BEEN BIOTITE+HORNBLENDE, COMPLETELY
ALTERED TO CLAY.MINS;
KFELDSPAR ( 1%)
Size(mm): 0.8-0.48
Groundmass - PLAGIOCLASE ( 30%)
Size(mm): 0.15X0.03 Morphology: LATHS
APPROX COMP AN25;
GLASS ( 10%)
COMPLETELY DEVITRIFIED AND NOW REPLACED BY CLAYS;
QUARTZ ( 11%)
ALKALI FELDSPAR ( 18%)
Morphology: ANHEDRAL
Alteration - CLAY MINERALS ( 18%)
Location: INTERSTITIAL Replacing: MAFICS,GLASS
Location: GLASS,PHENOS
Leg : 57 Top/Bottom Interval(mm): 730/ 740 Describer:
Hole: 439 Top of Core Depth(m) : 1125.00 Rock Type: IGNEOUS
Core: 35 Sample Midpoint(m) : 1125.74 Sect/Pc #: 1/
ROCK = DACITE;
Texture: INTERSERTAL-INTERGRANULAR;
Where sampled: BOULDER*
Phenocrysts- PLAGIOCLASE ( 14%)
Size(mm): 2.2-1.3 Morphology: EUHEDRAL
APPROX COMP AN46;
HORNBLENDE ( TR%)
Size(mm): 0.7X0.2 Morphology: SUBHEDRAL
BROWNISH GREEN PLEICHROISM;
MAFICS ( 7%)
Groundmass - PLAGIOCLASE ( 53%)
Size(mm): 0.08X0.03 Morphology: LATHS
APPROX COMP AN25;
GLASS ( 10%)
DEVITRIFIED;
QUARTZ ( 9%)
Morphology: ANHEDRAL
ALKALI FELDSPAR ( 7%)
Morphology: ANHEDRAL
Alteration - CLAY MINERALS ( 17%)
Location: INTERSTITIAL
Location: GLASS,PHENOS
MUSCOVITE ( TR%)
Leg : 57 Top/Bottom Interval(mm): 650/ 660 Describer:
Hole: 439 Top of Core Depth(m) : 1134.50 Rock Type: IGNEOUS
Core: 36 Sample Midpoint(m) : 1136.66 Sect/Pc #: 2/
ROCK = HORNBLENDE DACITE;
Texture: INTERSERTAL-HYALOOPHITIC;
Where sampled: BOULDER*
Phenocrysts- PLAGIOCLASE ( 18%)
Size(mm): 2.5X1.65
APPROX COMP AN40, ZONED, SIZE GIVEN IS A MAXIMUM;
BIOTITE ( TR%)
ALTERED;
MAFICS ( 11%)
MAY BE HORNBLENDE;
HORNBLENDE ( 3%)
Size(mm): 2.0X0.4
HIGHLY ALTERED;
KFELDSPAR ( 1%)
Size(mm): 2.0X0.9
Groundmass - PLAGIOCLASE ( 30%)
Size(mm): 0.15X0.04 Morphology: LATHS
APPROX COMP AN28;
MAGNETITE ( 5%)
Size(mm): TO 0.05
VERY FINE GRAINED;
GLASS ( 7%)
COMPLETELY ALTERED TO CLAY.MINS;
ORTHOPYROXENE ( TR%)
ID UNCERTAIN FOR OPX;
QUARTZ ( 8%)
Size(mm): 0.03 Morphology: ANHEDRAL
ALKALI FELDSPAR ( 17%)
Size(mm): 0.08X0.03 Morphology: ANHEDRAL
Alteration - CARBONATE ( TR%)
CLAY MINERALS ( 18%)
Location: INTERSTITIAL Replacing: BIOTITE,GLASS,HBL,MAFICS
Location: GLASS,PHENOS
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