Leg : 29 Top/Bottom Interval(mm): 350/1500 Analyst: Ovenshine, A.T.
Hole: 279A Sample Midpoint (m) : 195.50
Core: 12 Top of Core Depth (m) : 194.00
Sect: 1 Top of Section Depth(m): 194.35
LITHOLOGY: BASALT (VESICULAR);
Texture : THE UPPER 30 CM OF THE CORE IS SUBAPHANITIC TO VERY
FINE GRAINED, AT THE BASE OF CORE 12 SECTION 1 THE
BASALT IS FINE GRAINED;
Structure : SECTIONS 12-1 + 13-1 + 13-2 HAVE PENETRATED THE
UPPER 4.5 M OF A MASSIVE FLOW;
Comments : DARK GREY (N3), SEE CORE FORM AND LITHOLOGIC
DESCRIPTION IN THE INITIAL REPORTS FOR ADDITIONAL
INFORMATION;
Vesicles : VESICULAR AND AMYGDALOIDAL BASALT, CORE 12
SECTION 1 CONSISTS OF VESICULAR BASALT WITH 1
PERCENT PLAG PHENOCRYSTS;
Size(mm): 0.5 - 4 Percent: 10-40
IN THE UPPER 30 CM OF 12-1 VESICLES COMPRISE UP TO
40 PERCENT OF THE ROCK, THE VESICLES DECREASE
IN ABUNDANCE DOWN CORE SO THAT AT THE BOTTOM OF
CORE 12 SECTION 1 THEY COMPRISE LESS THAN 10
PERCENT OF THE VOLUME, VESICLES RANGE FROM
0.5 TO 4 MM IN DIAMETER AVERAGING 1.5 MM;
Location: Filling: CALCITE, PYRITE
Location: Filling: ZEOLITE, CHLORITE
APPROXIMATELY 90 PERCENT OF THE VESICLES ARE
UNFILLED, 3 PERCENT ARE PARTIALLY OR ENTIRELY
FILLED WITH WHITE CALCITE, 4 PERCENT HAVE 0.5 MM
THICK LININGS OF QUESTIONABLE BLUE ZEOLITE AND
3 PERCENT ARE FILLED WITH QUESTIONABLE CHLORITE,
RARE SUBHEDRAL PYRITE CRYSTALS OCCUR IN THE
VESICLES, IDENTITY UNCERTAIN FOR ZEOLITE AND
CHLORITE;
Phenocrysts: PLAGIOCLASE ( 1%)
CORE 12 SECTION 1 CONSISTS OF VESICULAR BASALT
WITH 1 PERCENT PLAG PHENOCRYSTS;
FELDSPAR ( < 1%)
Size(mm): TO 4.0
BASALT OF 12-1 CONSISTS OF LESS THAN OR EQUAL TO
1 PERCENT OF WHITE FELDSPAR PHENOCRYSTS, RANGING
TO 4 MM IN LENGTH IN A FINE GRAINED GROUNDMASS;
Groundmass : FELDSPAR ( 60%)
FELDSPAR LATHS (60 PERCENT) IN FINE GRAINED
GROUNDMASS;
PYROXENE
IDENTIFICATION UNCERTAIN IN FINE GRAINED
GROUNDMASS;
OLIVINE
IDENTIFICATION UNCERTAIN IN FINE GRAINED
GROUNDMASS;
GLASS
IDENTIFICATION UNCERTAIN IN FINE GRAINED
GROUNDMASS;
Replacement: CALCITE
IN VESICLES;
PYRITE
IN VESICLES;
ZEOLITE
IDENTIFICATION UNCERTAIN IN VESICLES;
CHLORITE
IDENTIFICATION UNCERTAIN IN VESICLES;
Leg : 29 Top/Bottom Interval(mm): 700/1500 Analyst: Ovenshine, A.T.
Hole: 279A Sample Midpoint (m) : 200.50
Core: 13 Top of Core Depth (m) : 199.00
Sect: 1 Top of Section Depth(m): 199.70
LITHOLOGY: BASALT;
Texture : SECTIONS 13-1 AND 13-2 CONSIST OF FINE GRAINED
BASALT WITH RARE VESICLES AND PHENOCRYSTS, CORE 13
SECTION 1 CONSISTS OF THE SAME ROCK AS CORE 12
SECTION 1 BUT WITH NO OR FEW PHENOCRYSTS AND
VESICLES;
Structure : SECTIONS 12-1 + 13-1 AND 13-2 HAVE PENETRATED THE
UPPER 4.5 M OF A MASSIVE FLOW;
Alteration : SEE CODE O (OTHER INFORMATION);
Comments : SECTIONS 13-1 AND 13-2 CONSIST OF THE SAME ROCK AS
CORE 12 SECTION 1 BUT WITH NO OR FEW PHENOCRYSTS
OR VESICLES, THE BASALT IS ALMOST FRIABLE AND MANY
OF THE CORE SEGMENTS HAVE BECOME BARREL SHAPED AS A
RESULT OF THE CORING PROCESS - THIS MAY SUGGEST
CONSIDERABLE GLASS IN THE GROUNDMASS OR A MODERATE
TO ADVANCED DEGREE OF ALTERATION, CORE 13 SECTION 1
CONSISTS OF 16 PIECES OF BASALT, ALTHOUGH THERE IS A
A GAP - ENOUGH OF THE CORE WAS RECOVERED TO SHOW
THAT THE ROCK OF THIS CORE GRADES LITHOLOGICALLY
INTO THE ROCK OF CORE 12 SECION 1;
Vesicles : CORE 13 SECTION 1 CONSISTS OF THE SAME ROCK AS
CORE 12 SECTION 1 BUT WITH NO OR FEW PHENOCRYSTS
AND VESICLES;
Groundmass : GLASS
POSSIBLY CONSIDERABLE GLASS IN THE GROUNDMASS;
Leg : 29 Top/Bottom Interval(mm): 0/1500 Analyst: Ovenshine, A.T.
Hole: 279A Sample Midpoint (m) : 202.00
Core: 13 Top of Core Depth (m) : 199.00
Sect: 2 Top of Section Depth(m): 200.50
LITHOLOGY: BASALT;
Texture : NON-VESICULAR, NON-PORPHYRITIC, FINE GRAINED BASALT,
SECTIONS 13-1 AND 13-2 CONSIST OF FINE GRAINED
BASALT WITH RARE VESICLES AND PHENOCRYSTS;
Structure : SECTIONS 12-1 + 13-1 + 13-2 HAVE PENETRATED THE
UPPER 4.5 M OF A MASSIVE FLOW;
Alteration : SEE CODE O (OTHER INFORMATION);
Comments : CORE 13 SECTION 2 HAS BASALT WITH 20 PIECES
COMPLETELY FILLING SECTION AND IS IDENTICAL
LITHOLOGICALLY TO CORE 13 SECTION 1 AND THE
NON-VESICULAR + NON-PORPHYRITIC ROCK OF THE
BOTTOM OF CORE 12 SECTION 1, THE BASALT IS
ALMOST FRIABLE AND MANY OF THE CORE SEGMENTS
HAVE BECOME BARREL SHAPED AS A RESULT OF THE
CORING PROCESS - THIS MAY SUGGEST CONSIDERABLE
GLASS IN THE GROUNDMASS OR A MODERATE TO
ADVANCED DEGREE OF ALTERATION;
Vesicles : CORE 13 SECTION 2 CONSISTS OF THE SAME ROCK AS
CORE 12 SECTION 1 BUT WITH NO OR FEW PHENOCRYSTS
AND VESICLES;
Groundmass : GLASS
POSSIBLY CONSIDERABLE GLASS IN THE GROUNDMASS;
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