Leg : 60 Top/Bottom Interval(mm): 1180/1200 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: IGNEOUS
Core: 1 Sample Midpoint(m) : 2.69 Sect/Pc #: 2/
ROCK = FELDSPATHIC GABBRO;
Texture: GRANOBLASTIC
TEX UNCERTAIN,SLIGHT INDICATION OF FOLIATION*
Groundmass - PLAGIOCLASE ( 40%)
Size(mm): 0.5-1.0
APPROX COMP AN60,FRESH;
CLINOPYROXENE ( 40%)
Size(mm): 0.3-1.0
FRESH,WITH EXSOLUTION LAMELLAE OF OPX;
ORTHOPYROXENE ( 20%)
Size(mm): 0.3-1.0
FRESH,WITH CPX EXSOLUTION LAMELLAE*
Alteration - CLAY MINERALS
SEVERAL FRACTURES RUNNING THROUGH SLIDE BEARING
CLAYS(?) BUT OTHERWISE SECONDARY MINS ARE ABSENT*
Leg : 60 Top/Bottom Interval(mm): 340/ 370 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: UNIDENTIFIED
Core: 1 Sample Midpoint(m) : 3.36 Sect/Pc #: 3/
ROCK = POLYMICT BRECCIA
SECTION CONSISTS OF TWO CLASTS,ONE LARGE OPX-CPX
PLAG GABBRO(2.0X2.5CM) + ONE BASALTIC(1.0X0.5CM) +
FINE-GRAINED GRANULATED GABBROIC MATERIAL AS A
MATRIX,GABBROIC CLAST HAS CUMULATE TEX AND COMP
OF PLAG(45%) + CPX(30%) + OPX(10%) + ONE LARGE
QUARTZ VEIN(0.5CM WIDE),BASALTIC CLAST CONSISTS OF
FRESH PLAG(30%) + INTERSTITIAL GLASS(27%) +
VESICLES(30%) + CPX(10%) + MAGN(3%),BRECCIA MATRIX
INCLUDES ZEOLITES + AMPHS + PYXS + ANTIGORITE +
GABBROIC FRAGS + VERY FINE GRAINED COMMINUTED
MATERIAL*
Alteration - TALC
Replacing: OPX
CHLORITE
Replacing: OPX
CLAY MINERALS
Replacing: CPX
QUARTZ
Leg : 60 Top/Bottom Interval(mm): 470/ 480 Describer: Sharaskin, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: IGNEOUS
Core: 1 Sample Midpoint(m) : 3.48 Sect/Pc #: 3/
ROCK = METABASALT;
Texture: PSEUDOSPHERULITIC-PSEUDOHYALOPILITIC;
Where sampled: COBBLE IN SEDIMENTS*
Phenocrysts- PLAGIOCLASE ( TR%)
Size(mm): TO 0.15 Morphology: LATHS
ONLY SINGLE GRAIN IN THE SLIDE;
CLINOPYROXENE ( TR%)
Size(mm): TO 0.17 Morphology: SKELETAL
APPROX COMP AUGITE,TWO GRAINS IN THE SLIDE*
Groundmass - GLASS
TOTALLY ALTERED,ORIGINALLY VESICULAR+SPHERULITIC+
HYALOPILITIC*
Alteration - CLAY MINERALS ( 97%)
Location: THROUGHOUT
QUARTZ ( 3%)
Location: VESICLES AND
Location: MICROXLN
ZEOLITE ( 3%)
Location: VEINS
VEINS UP TO 0.5MM THICK;
EPIDOTE ( <1%)
Location: MESOSTASIS
TINY GRAINS IN MICROXLN*
Vesicles -
Size(mm): 0.01-0.5
Percent: 3
Location: THROUGHOUT
Filling: QUARTZ
Shape: IRREGULAR
Leg : 60 Top/Bottom Interval(mm): 740/ 750 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: IGNEOUS
Core: 1 Sample Midpoint(m) : 3.75 Sect/Pc #: 3/
ROCK = APHYRIC BASALT;
Texture: INTERSERTAL*
Phenocrysts- PLAGIOCLASE ( TR%)
Size(mm): TO 0.5 Morphology: SUBHEDRAL
APPROX COMP AN70-80,UNALTERED;
CLINOPYROXENE ( TR%)
Size(mm): 0.2-0.5 Morphology: EUHEDRAL
APPROX COMP UNCERTAIN,FRESH LOOKING*
Groundmass - PLAGIOCLASE ( 20%)
Size(mm): 0.1-1.0 Morphology: BLOCKY-ACICULAR
APPROX COMP AN65;
CLINOPYROXENE ( 15%)
Size(mm): 0.1-0.3 Morphology: ACICULAR-SKELETAL
MAGNETITE ( 2%)
Size(mm): 0.01-0.13 Morphology: SUBHEDRAL
Alteration - CLAY MINERALS ( 53%)
Location: MESOSTASIS,
Location: VESICLES
Vesicles -
Size(mm): 0.05-0.5
Percent: 10
Location: THROUGHOUT
Filling: CLAY.MINS
Shape: IRREGULAR
Leg : 60 Top/Bottom Interval(mm): 850/ 860 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: IGNEOUS
Core: 1 Sample Midpoint(m) : 3.86 Sect/Pc #: 3/
ROCK = FELDSPATHIC GABBRO
PART OF BRECCIA;
Texture: CUMULATE*
Groundmass - PLAGIOCLASE ( 70%)
Size(mm): 0.1-1.0
APPROX COMP AN55,GENERALLY IN ADCUMULUS GROWTH
TEXTURE,GENERALLY NOT ZONED,UNALTERED;
CLINOPYROXENE ( 25%)
Size(mm): 0.1-1.0
GENERALLY INTERSTITIAL,MOSTLY ALTERED TO URALITE;
QUARTZ ( 3%)
Size(mm): 0.1-0.5
IN DISCRETE GRAINS AND IN VEINS WITH CHLORITE;
OTHER ( 2%)
INCLUDES SMALL AMOUNT OF POLYMICT IGNEOUS BRECCIA
MATERIAL ADHERED TO ONE SIDE OF FRAGMENT;
ORTHOPYROXENE
MAY HAVE BEEN PRESENT BEFORE URALITE ALTERATION*
Alteration - URALITE
Replacing: CPX
URALITE
Replacing: OPX
CHLORITE
Location: IN VEINS
QUARTZ ( 3%)
Location: VEINS
Leg : 60 Top/Bottom Interval(mm): 1210/1230 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: METAMORPHIC
Core: 1 Sample Midpoint(m) : 4.22 Sect/Pc #: 3/
ROCK = META-MICRODIABASE;
Texture: DIABASIC*
Groundmass - AMPHIBOLE ( 50%)
Size(mm): 0.1-0.5 Morphology: ANHEDRAL,FIBROUS
ACTINOLITE(?),REPLACING PYX;
PLAGIOCLASE ( 30%)
Morphology: TABULAR-BLOCKY
APPROX COMP AN50,PARTLY REPLACED BY CLAYS;
QUARTZ ( 15%)
Size(mm): 0.1-0.5
SOMETIMES IN MICROGRAPHIC INTERGROWTHS WITH
FELDSPARS;
MAGNETITE ( 5%)
Size(mm): 0.05-0.3 Morphology: SKELETAL-SUBHEDRAL
USUALLY ASSOCIATED WITH SPHENE AND AMPH*
Alteration - SPHENE ( TR%)
AMPHIBOLE
Replacing: PYX
CLAY MINERALS
Replacing: PLAG
Leg : 60 Top/Bottom Interval(mm): 100/ 110 Describer: Sharaskin, A.
Hole: 461A Top of Core Depth(m) : 0.00 Rock Type: METAMORPHIC
Core: 1 Sample Midpoint(m) : 6.00 Sect/Pc #: CC/
ROCK = METABASALT;
Texture: PSEUDOHYALOPILITIC-PSEUDOSPHERULITIC;
Where sampled: COBBLE IN SEDIMENTS*
Groundmass - MICROCRYST GROUNDMASS ( 70%)
TOTALLY ALTERED TO CLAYS;
PLAGIOCLASE ( 25%)
Size(mm): TO 0.2
MAGNETITE ( 5%)
Size(mm): 0.01-0.03
CLINOPYROXENE ( <1%)
Size(mm): TO 0.1 Morphology: RELICTS
RELICTS OF CRYSTALLITES*
Alteration - CLAY MINERALS ( 97%)
Location: VESICLES, Replacing: EVERYTHING
Location: MESOSTASIS
CHLORITE ( 3%)
Replacing: CPX
PSEUDOMORPHS AFTER CPX GRAINS*
Vesicles -
Size(mm): 0.03-0.5
Percent: 7
Location: THROUGHOUT
Filling: CLAY.MIN
Shape: ROUND
SOME VERY LARGE IRREGULAR VESICLES ARE PRESENT*
Leg : 60 Top/Bottom Interval(mm): 320/ 340 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: METAMORPHIC
Core: 2 Sample Midpoint(m) : 6.33 Sect/Pc #: 1/
ROCK = METABASALT
MICRODIABASE IS ALTERATE ROCK TYPE;
Texture: SUBOPHITIC
COARSE-GRAINED BASALT OR FINE-GRAINED MICRODIABASE*
Groundmass - PLAGIOCLASE ( 30%)
Size(mm): 0.1-0.6 Morphology: TABULAR-BLOCKY
APPROX COMP AN55,PARTLY ALTERED;
AMPHIBOLE ( 30%)
Size(mm): 0.1-0.7 Morphology: ANHEDRAL
GENERALLY FIBROUS,REPLACING CPX(?);
MICROCRYST GROUNDMASS ( 20%)
INTERGROWTH OF QUARTZ + FELDSPAR,HIGHLY ALTERED;
QUARTZ ( 10%)
Size(mm): 0.1-0.5
OFTEN FRACTURED,OCCUR THROUGHOUT ROCK;
MAGNETITE ( 8%)
Size(mm): 0.05-0.3
ASSOCIATED WITH AMPHIBOLE*
Alteration - EPIDOTE ( 2%)
Location: SCATTERED
AMPHIBOLE
Replacing: CPX
Leg : 60 Top/Bottom Interval(mm): 340/ 350 Describer: Sharaskin, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: METAMORPHIC
Core: 2 Sample Midpoint(m) : 6.35 Sect/Pc #: 1/
ROCK = METABASALT
AMPHIBOLITE;
Texture: POIKILOBLASTIC*
Groundmass - PLAGIOCLASE ( 60%)
POIKILOBLASTS OF PLAG(ANDESINE)FORMS GRANOBLASTIC
AGGREGATES TOGETHER WITH QUARTZ AND INCLUDES MAGN
GRAINS AND AMPH NEEDLES AND PLAG LATHS,FOLIATION
IS VERY WEAK,SOME EPIDOTE IS ALSO PRESENT;
HORNBLENDE ( 25%)
QUARTZ ( 7%)
MAGNETITE ( 7%)
Alteration - EPIDOTE
AMPHIBOLE
Leg : 60 Top/Bottom Interval(mm): 850/ 860 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: IGNEOUS
Core: 2 Sample Midpoint(m) : 6.86 Sect/Pc #: 1/
ROCK = SIDEROMELANE;
Texture: HOLOHYALINE*
Groundmass - GLASS ( 98%)
MOSTLY DEVITRIFIED(STILL ISOTROPIC) AND PARTLY
ALTERED TO CLAYS IN VESICLES AND ALONG VEINS,
FRESH;
PLAGIOCLASE ( 1%)
Size(mm): 0.01-0.2 Morphology: ACICULAR
APPROX COMP UNCERTAIN*
Alteration - CLAY MINERALS
Location: VESICLES, Replacing: GLASS
Location: ALONG VEINS
Leg : 60 Top/Bottom Interval(mm): 950/ 960 Describer: Sharaskin, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: METAMORPHIC
Core: 2 Sample Midpoint(m) : 6.96 Sect/Pc #: 1/
ROCK = METABASALT;
Texture: PSEUDOSUBOPHITIC;
Where sampled: COBBLE IN DRILLING BRECCIA*
Phenocrysts- PLAGIOCLASE ( TR%)
Size(mm): TO 0.2 Morphology: EUHEDRAL
APPROX COMP AN70,GLOMEROCRYSTS;
CLINOPYROXENE ( TR%)
Size(mm): TO 0.2 Morphology: EUHEDRAL
APPROX COMP AUGITE,SOMETIMES GLOMEROCRYSTS*
Groundmass - MICROCRYST GROUNDMASS ( 67%)
INCLUDES PYX MICROLITES;
PLAGIOCLASE ( 25%)
Size(mm): TO 0.3
APPROX COMP UNCERTAIN;
QUARTZ ( 5%)
Size(mm): 0.01-0.3
SECONDARY,SEPARATE GRAINS AND AGGREGATES;
MAGNETITE ( 3%)
Size(mm): 0.01-0.1
Alteration - CLAY MINERALS ( 90%)
Location: MESOSTASIS
QUARTZ ( 5%)
Location: MESOSTASIS,
Location: VESICLES
EPIDOTE ( 1-3%)
Location: MESOSTASIS
Vesicles -
Size(mm): 0.05-1.0
Percent: 10-15
Location: THROUGHOUT
Filling: QUARTZ,MINOR
Shape: SUBROUND-
Filling: CLAY.MINS
Shape: IRREGULAR
Leg : 60 Top/Bottom Interval(mm): 1050/1070 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: IGNEOUS
Core: 2 Sample Midpoint(m) : 7.06 Sect/Pc #: 1/
ROCK = GABBRO;
Texture: GRANOBLASTIC*
Groundmass - PLAGIOCLASE ( 45%)
Morphology: EUHEDRAL-SUBHEDRAL
APPROX COMP AN55 ZONED TO AN25 ON RIMS,INCIPIENTLY
ALTERED TO SERICITE;
AMPHIBOLE ( 35%)
Size(mm): 0.3-2.0 Morphology: ANHEDRAL
ACTINOLITE-TREMOLITE FILLING INTERSTITIAL AREAS
BETWEEN PLAG,OFTEN COMPLEXLY TWINNED,PROBABLY
REPLACEMENT OF CPX;
QUARTZ ( 8%)
Morphology: ANHEDRAL
INTERSTITIAL,SOMETIMES IN MICROGRAPHIC
INTERGROWTHS WITH FELDSPAR;
MAGNETITE ( 5%)
Size(mm): TO 1.0 Morphology: EQUANT
GENERALLY LARGE(1.0MM)GRAINS;
CHLORITE ( 5%)
Size(mm): <0.5
IN SMALL CLUMPS,PARTLY ALTERATION PRODUCT OF AMPH;
CLINOPYROXENE ( 2%)
REMNANTS MOSTLY REPLACED BY AMPH;
EPIDOTE ( TR%)
AS ALTERATION PRODUCT OF AMPH;
SPHENE
ASSOCIATED WITH LARGE MAGN GRAINS*
Alteration - AMPHIBOLE
Replacing: CPX
SERICITE
Replacing: PLAG
CHLORITE
Replacing: AMPH
EPIDOTE
Replacing: AMPH
Leg : 60 Top/Bottom Interval(mm): 150/ 160 Describer: Meijer, A.
Hole: 461A Top of Core Depth(m) : 6.00 Rock Type: METAMORPHIC
Core: 2 Sample Midpoint(m) : 7.59 Sect/Pc #: CC/
ROCK = EPIDOSITE
OBSERVER STATES THIS IS A WEIRD SLIDE*
Groundmass - EPIDOTE
NEARLY PURE EPIDOTE OR MINERAL OF SAME GROUP,IN A
FINE GRAINED MASS,LESSER AMOUNT OF THE MINERAL
WITH VERY LOW BIREFRINGENCE AND UNDULATORY
EXTINCTION-POSSIBLY A ZEOLITE*
Alteration - EPIDOTE
IDENTITY UNCERTAIN;
ZEOLITE
IDENTITY UNCERTAIN*
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