Leg : 43 Top/Bottom Interval(mm): 0/1460 Analyst: Houghton, R.
Hole: 387 Sample Midpoint (m) : 793.36
Core: 50 Top of Core Depth (m) : 791.90
Sect: 1 Top of Section Depth(m): 791.90
LITHOLOGY: PLAG MODERATELY PHYRIC BASALT;
Piece No. : PCE 1 (1-30), 2 (30-41), 3 (42-51), 4 (51-62),
5 (62-70), 6 (70-76), 7 (76-81), 8 (81-94),
9 (94-101), 10 (101-107), 11 (107-115),12 (115-130),
13 (130-132), 14 (132-137), 15 (137-146);
Texture : HYPOCRYSTALLINE,FINE-GRAINED,LOCALLY GRAINS OF DARK
BLACK GLASS ARE VISIBLE,PHYRIC;
Structure : ENCLOSURES OF 10R4/2 (GRAYISH RED) TO 10R3/4
(DARK REDDISH BROWN) "BAKED" CLUSTERS UP TO 6 CM
LONG LOCALLY ABUNDANT PARTIAL ASSIMILATION OF EDGES
OF ENCLOSURES VISIBLE,UPPER SURFACES OF ENCLOSURES
COMMONLY RIMMED BY 10YR7/4(GRAYISH ORANGE) ON THE
UPPER SURFACE AND BY A CHLORITE ZONE IN THE BASALT
BELOW,ENCLOSURES ARE ALSO FREQUENTLY ASSOCIATED WITH
CALCITE VEINS BEING "INTRUDED" ALONG THEM,IN PCE 1
UPPER SURFACE AND CORE ABOVE 20CM HEAVILY VEINED
WITH CALCITE-LOCALLY VEIN INCLUDES GRAYISH RED
SEDIMENT+BENDS AND BANDS OF CHLORITE-THE LATTER
PROBABLY PULLED AWAY FROM VEIN WALLS. ONE SUCH
CHLORITE BAND HAD THE SAME SNAKE-LIKE BENDS AS THE
WALLROCK NEAR IT.VEIN EXPANDS AT ITS UPPER SURFACE
AND CONTAINS CLASTS OF BASALT TO 5MM AND HAS
GREENISH BLACK SELVEGE (0-30CM), PCE 2 IS BASALT AS
ABOVE,NO SEDIMENT OR OBVIOUS GLASS,CALCITE VEINS
CONTAIN CLACITE CRYSTALS,IN PCE 3 CALCITE VEINS TO
38MM WIDE,SAMPLES EXTENSIVELY VEINED WITH CALCITE,
UPPER SURFACE OF 3A IS ALL VEIN-NO SEDIMENT
ENCLOSURES,IN PCE 4 MASSIVE DARK BASALT WITH MINOR
CALCITE VEIN AT BASE WITH CHLORITE RIM,IN PCE 5
THREE INTERLOCKING FRAGMENTS OF DARK BASALT WITH
MINOR VEINING ALONG FRAGMENT BOUNDARIES,IN PCE 6
TWO FRAGMENTS OF DARK BASALT WITH A 45.7X19.4X16.8MM
ENCLOSURE OF DARK REDDISH BROWN "BAKED" CLAYSTONE,
CLAST SHOWS SIGNS OF PARTIAL ASSIMILATION,UPPER
MARGIN RIMMED BY A 0.3MM LAYER OF GRAYISH ORANGE
SEDIMENT ALTERATION, PCE 7 INCLUDES COARSELY
CRYSTALLINE CALCITE VEIN IN UPPER SURFACE-MINOR
2.6MM SEDIMENT ENCLOSURES-AT BASE OF 7B IS AN
ENCLOSURE OF DARK REDDISH BROWN SEDIMENT 15.1X9.8MM,
PCE 8 IS MODERATELY CALCITE-VEINED DARK BASALT WITH
A LARGE DARK REDDISH BROWN SEDIMENT ENCLOSURE
18.7X11.2X22.2MM-THE ENCLOSURE HAS A THIN DARK GREEN
CONTACT WITH THE BASALT-CALCITE VEIN PARTIALLY CUT
ENCLOSURE,IN PCE 9 DARK MASSIVE BASALT WITH A MINOR
CHLORITIC ALTERATION ASSOCIATED WITH 3MM WIDE
CALCITE VEIN,PCE 10 IS WEDGE OF MASSIVE DARK BASALT,
IN PCE 11 FOUR UNRELATED PIECES OF DARK BASALT WITH
MINOR CALCITE VEINING,PCE 12 IS MASSIVE BASALT WITH
NOTICEABLE SCATTERED GRAINS OF GLASS,FOUR ENCLOSURES
OF DARK REDDISH BROWN SEDIMENT TO 55.5X25MM-
ENCLOSURES RIMMED BY CHLORITE AND SOMETIMES TOTALLY
ENCASED BY A CALCITE VEIN-VEINS ALSO COMMONLY HAVE
CHLORITIC CONTACTS WITH WALLROCK,PCE 13 IS A
60X20MM PARTIALLY ASSIMILATED ENCLOSURE OF DARK
REDDISH BROWN SEDIMENT WITH CHLORITIC CONTACTS IN
A DARK MASSIVE BASALT,PCE 14 IS DARK BASALT
HEAVILY VEINED WITH CALCITE-CHORITIC WALLROCK
MARGINS ARE MINOR,PCE 15 IS DARK MASSIVE BASALT
WITH MINOR CALCITE VEINING;
Comments : BETWEEN PCE 2 AND 3 ARE THREE SMALL FRAGMENTS OF
HOMOGENEOUS DARK BASALT,IN PCE 3 THREE FRAGMENTS
(A+B+C) WHICH EASILY FIT TOGETHER;
Phenocrysts: FELDSPAR ( <5%)
Size(mm): <2
LOCALLY REPLACED BY CALCITE,IN PCE 4 RARE
FELDSPAR PHENOS TO 3MM,FELDSPAR PHENOS TO 4.5MM
MORE COMMON IN PCE 10,FELDSPAR PHENOS TO 2.5MM
COMMON IN PCE 12,COMMON FELDSPAR PHENOS IN PCE 15;
Replacement: CHLORITE
CLAST IN PCE 6 BORDERED BY 3MM CHLORITE HALO IN
THE ENCLOSING BASALT,CHLORITE MINOR IN PCE 3;
CALCITE
Leg : 43 Top/Bottom Interval(mm): 0/1500 Analyst: Houghton, R.
Hole: 387 Sample Midpoint (m) : 794.90
Core: 50 Top of Core Depth (m) : 791.90
Sect: 2 Top of Section Depth(m): 793.40
LITHOLOGY: PLAG MODERATELY PHYRIC BASALT;
SAME AS DESCRIPTION FOR CORE 50-1;
Piece No. : PCE 1 (0-6), 2 (6-10), 3 (10-12), 4 (12-27),
5 (27-32), 6 (32-47), 7 (47-57), 8 (57-61),
9 (61-80), 10 (80-87), 11 (87-94), 12 (94-105),
13 (105-112), 14 (112-127), 15 (127-142),
16 (142-150);
Structure : PCE 2A CONTAINS PORTION OF CALCITE VEIN EXPOSING
ITS CHLORITE WALL,PCE HAS ENCLOSURE OF DARK REDDISH
BROWN CLAY IN MASSIVE BASALT-ENCLOSURE HEMMED BY A
CALCITE VEINLET ON ALL SIDES-CHLORITE INCLUSIONS
+ CALCITE + BASALT,IN PCE 4 SEDIMENT ENCLOSURES IN
CALCITE VEIN ABOUT 2MM THICK,IN PCE 6 UPPER BASALT
SURFACE CHLORITIZED AND SHEARED AS ALONG A FAULT,
MINOR CALCITE VEINING IN PCE 7,IN PCE 8 BASAL
PORTION INCLUDES AN ENCLOSURE OF SEDIMENT CONTINUOUS
WITH PCE 9,TOP PART OF PCE 9 CONTAINS SEDIMENT
ENCLOSURES WITH CHLORITE BOUNDARIES TO BASALT-MINOR
CHLORITE VEINING TOWARD BASE OF PIECE,IN PCE 11 FOUR
FRAGMENTS OF BASALT CONTAINING GLASS AND FELDSPAR
PHENOS WITH ENCLOSURES OF DARK REDDISH BROWN
SEDIMENT BOUNDED BY CHLORITE-SEDIMENT SHOWS SIGNS
OF PARTIAL ASSIMILATION AND CONTAINS "CLASTS" OF
BASALTIC MATERIAL INCLUDING ONE 32MM EUHEDRAL
FELDSPAR PHENO,MASSIVE BASALT WITH COMMON CALCITE
AND CHLORITE VEINLETS IN PCES 12 AND 13 AND RARE
MINOR CALCITE VEINLETS IN PCE 14,IN PCE 15 CALCITE
VEIN BECOMES CALCITE ENCLOSING SEDIMENT YIELDING
APPEARANCE OF SEDIMENTARY "DIKE" CUTTING BASALT-
CALCITE VEINS BOUNDED BY CHLORITE,IN PCE 16 SEDIMENT
ENCLOSURES IN CALCITE VEIN CONTINUOUS FROM ABOVE,
MASSIVE BASALT IN PCE 4;
Comments : THREE FRAGMENTS OF DARK MASSIVE BASALT COMPRISE
PCE 5;
Vesicles : Size(mm): Percent: <1
Location: Filling: CALCITE,CHLORITE
AMYGDULES IN PCE 16;
Phenocrysts: FELDSPAR
COMMON PHENOS TO 0.5CM IN PCE 1+4+6,PCES 14+16
CONTAIN PHENOS TO 2MM,PHENOS TO 6MM IN PCE 9,
PHENOS TO 2.5MM IN PCE 10,ONE 32MM EUHEDRAL PHENO
IN PCE 11;
Replacement: CHLORITE
CALCITE
Texture : GLASS VISIBLE IN PCE 6;
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