Leg : 17 Top/Bottom Interval(mm): 0/ 0 Describer: Moberly, R. Hole: 166 Top of Core Depth(m) : 250.00 Rock Type: TUFF Core: 23 Sample Midpoint(m) : 253.10 Sect/Pc #: CC/ ROCK = VITRIC TUFF ALTERED,DOMINATED BY LIGHT GLASS AND ALTERED GLASS,THE LIGHT GLASS MAINLY SPLINTERY ANGULAR SHARDS,COMMONLY FROTHY* Groundmass - PLAGIOCLASE SOME GRAINS, LAMINATION SHOWN BY BOTH GRAIN SIZE AND BY ALIGNMENT OF SOME ELONGATE GRAINS,MOST GRAINS APPROX .05MM,ALMOST CERTAINLY PYROCLASTIC* Alteration - CHLOROPHAEITE SERPENTINITE MANY GRAINS ALTERED TO TURBID GREEN OR BROWN CHLOROPHAEITE AND SERPENTINE; ANALCIME Location: CEMENT,VEINS COMMON AS A PATCHY CEMENT,AS VEINLETS AND AS IRREGULAR SPHERES IN THE CLAYEY(MONTMORILLONITE?) INTERGRANULAR PARTS OF THE ROCK* Leg : 17 Top/Bottom Interval(mm): 0/ 0 Describer: Moberly, R. Hole: 166 Top of Core Depth(m) : 270.00 Rock Type: TUFF Core: 25 Sample Midpoint(m) : 271.60 Sect/Pc #: CC/ ROCK = VITRIC TUFF ALTERED,FORAMINIFERAL* Groundmass - GLASS MAINLY ANGULAR GRAINS OF DARK GLASS,LARGELY ALTERED TO CHLOROPHAEITE AND RIMMED WITH A FILM OF FIBROUS ZEOLITE,POSSIBLY REWORKED FROM A NEARBY HYALOCLASTIC DEPOSIT,POSSIBLY PYROCLASTIC* Alteration - CALCITE SPHERES OF CALCITE(SOME SHOW "PSEUDOISOGYRES" AND PERFORATED TESTS OF FORAMS FILLED WITH SPARRY CALCITE)ABUNDANT,SOME PATCHY POIKILITIC CALCITE BUT MAINLY A MATRIX OF GREEN CLAY,AVERAGE GRAIN SIZE APPROX .1MM,FORAMS TO .2MM* Leg : 17 Top/Bottom Interval(mm): 1230/ Describer: Bass, M. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 308.23 Sect/Pc #: 1/ ROCK = PLAG-OL-CPX MICROPHYRIC BASALT SOURCE IS IR,SEE P.481,ALTERED; Texture: MICROPHYRIC,SPHERULITIC TO VARIOLITIC* Phenocrysts- PLAGIOCLASE MICROPHENOS,APPROX COMP AN64 TO AN75,MORE ABUNDANT THAN IN OL; OLIVINE Morphology: PSEUDOMORPHS MICROPHENOS,COMPLETELY ALTERED; PYROXENE MICROPHENOS* Groundmass - GLASS ALTERED TO YELLOW+ORANGE BROWN OR DEEP RED BROWN MONT* Alteration - MONTMORILLONITE Replacing: OL,GLASS BOWLINGITE; FERROUS OXIDE Replacing: OL,GLASS Leg : 17 Top/Bottom Interval(mm): 1230/ 0 Describer: Moberly, R. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 308.23 Sect/Pc #: 1/ ROCK = BASALT ALTERED; Texture: HYPOXTLLINE,SLIGHTLY VESICULAR,GLOMEROPHYRIC, VARIOLITIC TEXTURE GIVEN IS ORIGINAL TEXTURE* Phenocrysts- PLAGIOCLASE Size(mm): TO .5X.75 Morphology: LATHS APPROX COMP SODIC LABRADORITE,COMMONLY WITH PAINT BRUSH ENDS(ALKALIC OVERGROWTHS?); OLIVINE Size(mm): TO .35 NOW ANTIGONITE AND IDDINGSITE; OPAQUE MINERALS Morphology: EQUANT AUGITE Groundmass - PLAGIOCLASE Morphology: VARIOLITIC MICROLITES GLASS NOW SHEAVES OF MONTMORILLONITE AND BROWN CHLORITE, DUSTED WITH OPAQUES* Alteration - MONTMORILLONITE Location: AMYGDULES Replacing: GLASS CHLORITE Location: AMYGDULES Replacing: GLASS Vesicles - Size(mm): TO .5 Filling: MONT+CHLORITE+ Filling: HEMATITE ID UNCERTAIN FOR HEMATITE(RED-BROWN MINERAL). AMYGDULES* Leg : 17 Top/Bottom Interval(mm): 160/ 250 Describer: Bass, M. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 308.71 Sect/Pc #: 2/ ROCK = BASALT SOURCE IS IR,SEE P.481; Texture: CHILLED,MICROPHYRIC,GROUNDMASS GRADES FROM A GLASS SELVAGE THROUGH A SPHERULITIC LAYER (1CM Texture: K) TO FINE BOW-TIE OR SHEAF-LIKE VARIOLES TO ROCK = IAL PLAGIOCLASE CLUSTERS SET IN A MASS OF FINE FEATHERY PYROXENE VARIOLES AND ALTERED INTERSTITIAL GLASS* Groundmass - PLAGIOCLASE PYROXENE GLASS ALTERED GLASS (MONT) PROBABLY IN PART PALAG PRIOR DIAGENESIS* Alteration - PALAGONITE Replacing: GLASS MONTMORILLONITE Replacing: GLASS,OL IDDINGSITE Replacing: OL ESSENTIALLY NON-VESICULAR* Leg : 17 Top/Bottom Interval(mm): 720/ 740 Describer: Bass, M. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 310.73 Sect/Pc #: 3/ ROCK = PLAG-PYX-OL MICROPHYRIC BASALT SOURCE IS IR,SEE P.481; Texture: CHILLED, MICROPHYRIC* Phenocrysts- PLAGIOCLASE ( 8.4%) Size(mm): 0.25X0.03 PYROXENE ( 2.8%) Size(mm): 0.13X0.10 OLIVINE ( 2.3%) Size(mm): 0.19X0.12 Morphology: PSEUDOMORPHS Groundmass - OPAQUE MINERALS ( 11.6%) Size(mm): 0.35 Morphology: EQUANT,ELONGATE PYROXENE ( 74.8%) Morphology: FEATHERY VARIOLES MODAL ANALYSIS* Alteration - MONTMORILLONITE Location: CORES Replacing: PLAG,OL PLAG CORES,OL MICROPHENOS; IDDINGSITE Replacing: OL Vesicles - Percent: 0 Leg : 17 Top/Bottom Interval(mm): / Describer: Bass, M. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 311.60 Sect/Pc #: CC/ ROCK = COARSE-GRAINED BASALT OR FINE-GRAINED DIABASE SOURCE IS IR,SEE PP.481-482; Texture: APHYRIC,SUBVARIOLITIC GROUNDMASS,TEXTURALLY VARIABLE,WHERE RELATIVELY COARSE-GRAINED IS INTERGRANULAR OR RARELY SUBOPHITIC WHEREAS ELSEWHERE INTERGRANULAR TO INTERSERTAL VARIOLITIC MASS WITH ABUNDANT OPAQUE VEINS* Groundmass - PLAGIOCLASE ( 28.0%) Size(mm): 0.5X0.05 PYROXENE ( 20.2%) Size(mm): 0.12X0.12 OLIVINE ( 2.7%) Size(mm): 0.5X0.12 Morphology: PSEUDOMORPHS OPAQUE MINERALS ( 12.9%) Size(mm): 0.1X0.02 GROUNDMASS ( 36.2%) INCLUDES PYX+PLAG+OP.MINS IN AN ABUNDANT GREEN INTERSERTAL MASS OF INTERSERTAL MASS OF MONT, AT OTHER END ARE FEATHERY QUENCHED VARIOLES; AUGITE QUENCHED PYROXENE IS MAINLY SUBCALCIC AUGITE, MODAL ANALYSIS* Alteration - MONTMORILLONITE Location: CORES Replacing: PLAG CELADONITE Location: CORES Replacing: PLAG MONTMORILLONITE Replacing: PYX MONTMORILLONITE Replacing: OL CELADONITE Replacing: OL Vesicles - Size(mm): 0.35 Percent: .1 Filling: MONT Leg : 17 Top/Bottom Interval(mm): 0/ 0 Describer: Moberly, R. Hole: 166 Top of Core Depth(m) : 307.00 Rock Type: IGNEOUS Core: 29 Sample Midpoint(m) : 311.60 Sect/Pc #: CC/ ROCK = FINE DIABASE OR COARSE BASALT ALTERED,THIS SECTION CONSISTS OF THREE BANDS-GRAY, GREEN,BROWN* THE FOLLOWING IS A DESCRIPTION OF THE GRAY BAND:. THE GRAY BAND IS THE LEAST ALTERED AND HAS A DOLERITIC TEXTURE,IS FINE DIABASE IN GRAIN SIZE(TO 1MM) AND NON-VESICULAR; Groundmass - PLAGIOCLASE Size(mm): TO 1X.04 Morphology: LATHS ALBITE AND PERICLINE TWINS,CORE COMMONLY SERICTIZED? OR SAUSSURITIZED; PYROXENE INTERSTITIAL; OPAQUE MINERALS Morphology: EQUANT-BLADED EUHEDRAL COMMONLY CLUSTERED; OLIVINE ABUNDANT SERPENTINE PSEUDOMORPHS OF OL,THE FOLLOWING IS A DESCRIPTION OF THE GREEN BAND:; BASALT GENERALLY SAME AS GRAY BAND BUT VESICLES RIMMED WITH VERY FINE GRAINED BASALT AND CHLORITIC GROUNDMASS MORE COMMON,THE FOLLOWING DESCRIPTION IS FOR THE BROWN BAND:; PLAGIOCLASE Size(mm): TO .5 FINE GRAINED,INTERSTITIAL PART BROWN,COMMONLY RADIATING LIKE LARGE VARIOLITES; OPAQUE MINERALS Size(mm): TO .4X.03 Morphology: BLADES HEAVILY CHARGED WITH OPAQUES* Alteration - CHLORITE Location: VESICLES+ Location: GROUNDMASS MONTMORILLONITE Location: VESICLES THIS IS THE GREEN BAND* Vesicles - Size(mm): TO .7 Filling: CHLORITE+MONT Shape: IRREGULAR SOME RIMMED WITH BASALT* |
Cite as: Deep Sea Drilling Project (1989): Archive of Core and Site/Hole Data and Photographs from the Deep Sea Drilling Project (DSDP). National Geophysical Data Center, NOAA. doi:10.7289/V54M92G2 [access date]
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