Leg : 30 Top/Bottom Interval(mm): 730/ 740 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 236.00 Rock Type: IGNEOUS
Core: 16 Sample Midpoint(m) : 236.74 Sect/Pc #: 1/
ROCK = PLAG-OL PHYRIC BASALT;
Texture: PHYRIC,INTERSERTAL*
Phenocrysts- PLAGIOCLASE (15-20%)
Size(mm): <5 Morphology: EUHEDRAL
OFTEN AS GLOMEROCRYSTS OF UP TO 10 XTLS,SOME WEAK
OSCILLATORY ZONING,SOME SHOW RESORPTION ON EDGES,
ALSO DEFINITELY A CYCLIC HISTORY OF GROWTH-
RESORPTION-REGROWTH-ETC.,OFTEN EUHEDRAL PLAG
(APPROX COMP BYTOWNITE(>AN70))SHOW SODIC RIMS WITH
SHARP CONTACT WITH REST XTLS OF APPROX .005MM
THICKNESS,ABUNDANT MINERAL INCLUSIONS,ORIENTED IN
CORES OF PHENOS(USUALLY RESTRICTED TO INNER THIRD)
ID UNCERTAIN-UNUSUAL,VISUAL ESTIMATES OF ALL
PERCENTAGES;
OLIVINE ( 5%)
Size(mm): <1.5
PSEUDOMORPHS-REPLACED BY SERPENTINE+LESSER
CALCITE*
Groundmass - PLAGIOCLASE
Size(mm): <.2 Morphology: ACICULAR+HOLLOW
MAY HAVE BEEN GLASS INTERSTITIAL TO PLAG;
PYROXENE
DEFINITELY REPLACED BY CHLORITE;
OTHER
Size(mm): <.1 Morphology: CUBIC
DEEP RED MINERAL-ID UNCERTAIN(MAGNETITE ALTERED TO
HEMATITE,AL-CR SPINEL OR PEROVSKITE)*
Alteration - SERPENTINITE
Replacing: OL
CALCITE
Replacing: OL
CHLORITE
Location: PATCHES,VOIDS Replacing: GROUNDMASS IRREGULAR
Replacing: GLASS+MAFICS
ID UNCERTAIN FOR VOID FILLINGS AND GLASS
REPLACEMENT*
Leg : 30 Top/Bottom Interval(mm): 1160/ 0 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 236.00 Rock Type: IGNEOUS
Core: 16 Sample Midpoint(m) : 237.16 Sect/Pc #: 1/
ROCK = PLAG-OL PHYRIC BASALT;
Texture: PHYRIC,INTERSERTAL,INTERSTITIAL*
Phenocrysts- PLAGIOCLASE (15-20%)
SEE 30-287-16-1-73-74 AND 17-CC;
OLIVINE ( 0-<1%)
VERY DIFFICULT TO SPOT ANY POSSIBLE PSEUDOMORPHS
AFTER OL-IF ANY PRESENT DEFINITELY <1%*
Groundmass - PLAGIOCLASE
Size(mm): .2 Morphology: MICROLITES
PYROXENE
Size(mm): .04 Morphology: SUBVARIOLITIC+FAN-SHAPED
Morphology: PLUMOSE
QUITE FRESH;
MAGNETITE
Size(mm): <.025 Morphology: EUHEDRAL+CLOTS
OTHER
Size(mm): <.1 Morphology: EUHEDRAL CUBIC
DEEP RED-NOT OXIDIZED MAGN*
Alteration - CHLORITE
Replacing: GLASS
PROBABLY NO PYX CHLORITIZED AS PYX SO FRESH*
Leg : 30 Top/Bottom Interval(mm): 680/ 0 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 238.00 Rock Type: IGNEOUS
Core: 17 Sample Midpoint(m) : 240.18 Sect/Pc #: 2/
ROCK = PLAG PHYRIC BASALT;
Texture: PHYRIC,INTERSERTAL*
Phenocrysts- PLAGIOCLASE
OLIVINE ( 0%)
Groundmass - PLAGIOCLASE
Size(mm): .4-.5
MAGNETITE
Size(mm): <.05
PYROXENE
Morphology: RADIATING CLUSTERS
ABUNDANT,APPROX 2/3 ALTERED TO CHLORITE*
Alteration - CALCITE
Location: VEINS
CHLORITE
Location: VEINS
SERPENTINITE
Location: VEINS Replacing: FIBROUS
ID UNCERTAIN FOR SERPENTINE*
Leg : 30 Top/Bottom Interval(mm): 0/ 0 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 238.00 Rock Type: IGNEOUS
Core: 17 Sample Midpoint(m) : 242.60 Sect/Pc #: CC/
ROCK = PLAG-OL PHYRIC BASALT;
Texture: PHYRIC,INTERSERTAL,SUBOPHITIC
RATHER LIKE A DIABASIC TEXTURE*
Phenocrysts- OLIVINE ( 5.2%)
Size(mm): <2.5
FRESH,MEASURED ON LONG AXIS, ALL PERCENTAGES
DETERMINED BY POINT COUNT,FRESH BUT USUALLY HAVE
SERPENTINE ALONG THE FRACTURES,USUALLY 1/5-1/3 OF
XTL REPLACED;
PLAGIOCLASE
Size(mm): <2.5
APPROX COMP BYTOWNITE(>AN70),OFTEN GLOMEROCRYSTIC
WITHOUT OL PHENOS,MODERATE NORMAL ZONING AND
OCCASIONAL WEAK OSCILLATORY ZONING,ROUND CORES
AND THEIR ORIENTATION RELATIVE TO REST OF XTL
DEFINITELY INDICATE CYCLES OF RESORPTION AND
REGROWTH,CENTRAL AREAS USUALLY WITH LARGE ORIENTED
UNIDENTIFIED MINERAL INCLUSIONS(UNUSUAL)*
Groundmass - PLAGIOCLASE ( 25.6%)
Size(mm): .3-. Morphology: 4
PYROXENE ( 45%)
WELL DEVELOPED AS SINGLE XTLS,NO TENDENCY TO
TO DEMONSTRATE RADIATING HABIT;
OLIVINE ( 3%)
MAGNETITE ( 4%)
OTHER
Size(mm): <.1 Morphology: CUBIC
SPARE DEEP RED ISOTROPIC MINERAL SOMETIMES
INCLUDED IN OL USUALLY IN GROUNDMASS,PROBABLY
CR-SPINEL*
Alteration - CHLORITE
Location: GROUNDMASS
SMALL AMOUNT;
SERPENTINITE
Replacing: OL
Vesicles -
Size(mm): <.3
Percent: .4
Filling: CHLORITE
RARE AMYGDULES*
Leg : 30 Top/Bottom Interval(mm): 440/ 470 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 242.50 Rock Type: IGNEOUS
Core: 18 Sample Midpoint(m) : 242.96 Sect/Pc #: 1/
ROCK = PLAG-OL PHYRIC BASALT;
Texture: PHYRIC*
Phenocrysts- PLAGIOCLASE
OLIVINE
PSEUDOMORPHED BY CHLORITE+SOME UNKNOWN MINERAL,
APPEARS TO BE INTERMEDIATE STAGE IN ALTERATION,
CORES HAVE BROWNISH GRANULAR MINERAL WHICH GIVES
PARALLEL EXTINCTION*
Groundmass - PLAGIOCLASE
Size(mm): .2
AVE. LENGTH GIVEN;
PYROXENE
FRESH,SHOWS DISTINCT SUBVARIOLITIC HABIT;
MAGNETITE
GLASS
VERY POSSIBLE THAT PRESENT CHLORITE WAS GLASS;
OTHER
Size(mm): <.07 Morphology: EUHEDRAL+SQUARE OUTLINES
DEEP RED ABUNDANT MINERAL*
Alteration - CHLORITE
Location: VEINS, Replacing: OL,GLASS
Location: GROUNDMASS
ABUNDANT IN GROUNDMASS;
CALCITE
Location: VEINS
CHLORITE>>CALCITE*
Vesicles -
Size(mm): <.3
Filling: CHLORITE
RARE AMYGDULES*
Leg : 30 Top/Bottom Interval(mm): 480/ 500 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 242.50 Rock Type: IGNEOUS
Core: 18 Sample Midpoint(m) : 242.99 Sect/Pc #: 1/
ROCK = PLAG-OL SPARSELY PHYRIC BASALT;
Texture: SPARSELY PHYRIC,INTERSERTAL,HOLOXTLLINE*
Phenocrysts- PLAGIOCLASE ( 1%)
Size(mm): <1.5
MEASURED ALONG LONG AXIS,APPROX COMP AN70 BY
CARLSBAD-ALBITE METHOD;
OLIVINE
Size(mm): <.6
CHLORITE PSEUDOMORPHS AFTER OL,MEASURED ALONG LONG
AXIS*
Groundmass - PLAGIOCLASE
Size(mm): <.03
PYROXENE ( 0%)
CHLORITIZED,APPEARS WERE IN BUNDLES OR
SUBVARIOLITIC;
GLASS
NOT POSSIBLE TO TELL IF WAS ORIGINALLY PRESENT
BECAUSE OF CHLORITIZATION*
Alteration - CHLORITE
Replacing: PYX+OL+GLASS
Vesicles -
Size(mm): <1.5
Percent: 2
Filling: CHLORITE
Shape: ROUND+
Shape: IRREGULAR
AMYGDULES,SIZE IS FOR ROUND-FOR IRREGULAR IS <4MM*
Leg : 30 Top/Bottom Interval(mm): 1460/1500 Describer: Stoeser, D.
Hole: 287 Top of Core Depth(m) : 242.50 Rock Type: IGNEOUS
Core: 18 Sample Midpoint(m) : 243.98 Sect/Pc #: 1/
ROCK = PLAG-OL SPARSELY PHYRIC BASALT;
Texture: SPARSELY PHYRIC,DIABASIC,FINE-GRAINED*
Phenocrysts- PLAGIOCLASE ( 2%)
Size(mm): <1 Morphology: TABULAR
CORE APPROX COMP AN70 BY CARLSBAD-ALBITE METHOD,
ODD CROSS-SECTIONS OR EACH QUADRANT WILL GO
EXTINCT AT DIFFERENT ANGLE,OFTEN NORMALLY ZONED,
2V 85DEGREES;
OLIVINE ( 1%)
Size(mm): <1
PSEUDOMORPHED BY SERPENTINE?+CACO3 AND CHLORITE,
OUTLINES POORLY PRESERVED,OL PHENO OCCASIONALLY
INTERGROWN WITH PLAG PHENO*
Groundmass - PLAGIOCLASE ( 40%)
Morphology: ACICULAR
SQUARE CROSS-SECTIONS;
MAGNETITE ( 5%)
% DIFFICULT TO ESTIMATE(ALL PERCENTAGES BY VISUAL
ESTIMATE),QUENCH(APPROX DENDRITIC)*
Alteration - CHLORITE
Replacing: PYX,OL
PLAG ONLY SLIGHTLY AFFECTED;
CALCITE
Location: VEINS
SERPENTINITE
Replacing: OL
Vesicles -
Size(mm): <.5
Percent: <1
Filling: CHLORITE
Shape: ROUND
AMYGDULES,PERFECTLY ROUND*
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