Leg : 7 Top/Bottom Interval(mm): 0/ 0 Describer: Heath, R.
Hole: 62 Top of Core Depth(m) : 580.00 Rock Type: IGNEOUS
Core: 8 Sample Midpoint(m) : 580.10 Sect/Pc #: CC/
ROCK = ALTERED BASALT
Texture: HYPOCRYSTALLINE,HYPIDIOMORPHIC*
DARK GRAY,RATHER WEATHERED;
Groundmass - PLAGIOCLASE
Size(mm): .7X.07 Morphology: LATHS
HEAVILY ALTERED TO PALE GREEN MONTMORILLONITE,
APPROX COMP AT LEAST AN70(BY MICHEL-LEVY METHOD)
BUT ACCURATE DETERMINATIONS DIFFICULT DUE TO
ALTERATION;
PYROXENE
Size(mm): .5 Morphology: ANHEDRAL
RARE EQUIDIMENSIONAL,IN GROUNDMASS OF PLAG+ALTERED
GLASS,ALMOST COLORLESS,NON-PLEOCHROIC,HEAVILY
ALTERED TO PALE GREEN MONTMORILLONITE;
OLIVINE
OPAQUE MINERALS
ORIGINALLY ROCK CONTAINED OL AND ILMENITE OR MAGN
(AS EVIDENCED BY LIMONITE AND IDDINSITE
PSEUDOMORPHS),GROUNDMASS CONSISTS OF ROUNDED .1-.2
MM BLEBS OF PALE GREEN MONTMORILLONITE? AND
PERHAPS SOME CHLORITE(ORIGINALLY MICROVESICLES?)
SEPARATED BY BUNCHES AND .1-.2MM FANS OF PALE
BROWN CHLORITE,APPARENTLY PRESERVING THE ORIGINAL
TEXTURES OF THE GLASS*
Alteration - CHLORITE
Location: GROUNDMASS,
Location: VESICLES
MONTMORILLONITE
Location: GROUNDMASS,
Location: VESICLES
ZEOLITE
Location: VESICLES
CARBONATE
Location: VEINS
NEAR THE BOUNDARY WITH CARBONATE VEINS THE
GROUNDMASS IS MORE LIMONITE STAINED AND GREEN
CHLORITE AND ZEOLITE ARE MORE ABUNDANT IN
VESICLES. THE CARBONATE VEINS CONSIST OF FORAMS +
COCCOLITHS,APPARENTLY LITTLE AFFECTED BY
INCORPORATION INTO THE BASALT,ALTHOUGH SOME EMPTY
FORAM CHAMBERS ARE FILLED WITH PALE GREEN CHLORITE
AND/OR MONTMORILLONITE.PORTIONS OF THE MATRIX ARE
ALSO IMPREGNATED WITH THIS MATERIAL*
LARGER VESICLES CONTAIN .04-.07MM RIMS OF CHLORITE
AND MONTMORILLONITE?(PALE GREEN)GRADING TO .05-.07
MM BLADES OF ALMOST COLORLESS MONTMORILLONITE
NORMAL TO VESICLE WALLS,AND FINALLY TO CORES
OF ANHEDRAL TO SUBHEDRAL LATHS OF ZEOLITE UP TO
.3MM IN LENGTH*
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