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Core data from the Ocean Drilling Program legs 101-129
ODP hard-rock thin section description - verbose form
leg : 104 section: 03 unit/subunit : 0001
hole: 642E top int: 061 cm observer code: LEH
core: 005R pieces: 008
rock name: Sparsely olivine plagioclase phyric basalt
where sampled: Flow unit 1
***** PHENOCRYSTS *****
Olivine present % 3-5 original % 3-5 size .1-.4
morphology : Euhedral
comments : Completely altered to iddingsite.
***** GROUNDMASS *****
Opaques present % 2-3 original % 2-3 size <0.1
****** VESICLES *****
Type: Vesicles %: ~5
shape : Round
Sometimes difficult to discriminate from altered groundmass.
****** SECONDARY MINERALIZATION ******
mineral name: Clays/carbonate percent: 85-90
replacement: Plagioclase, clinopyroxene
comments : Groundmass virtually completely altered.
****** OVERALL COMMENTS ******
Altered.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0002
hole: 642E top int: 036 cm observer code: LEH
core: 007R pieces: 008
rock name: Sparsley plagioclase phyric basalt
texture: Intersertal
where sampled: Flow 2
***** PHENOCRYSTS *****
Plagioclase present % <1 original % <1 size 1.5
morphology : Prismatic
comments : Altered to clays.
***** GROUNDMASS *****
Altered to clays.
Plagioclase present % 30 original % 30 size 0.05-<0.5
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 40-45
replacement: Plagioclase, vesicle rims
comments : Interstitial, slightly pleoch.,
relatively high birefringence.
****** OVERALL COMMENTS ******
Radial, fibrous (quenched textures?) in matrix.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0004
hole: 642E top int: 055 cm observer code: LEH
core: 011R pieces: 002
rock name: Sparsely clinopyroxene plagioclase phyric basalt
texture: Intersertal
where sampled: Flow 4
***** PHENOCRYSTS *****
Plagiocalse present % <1 original % <1 size 0.4
morphology : Prismatic
***** GROUNDMASS *****
Plagioclase present % 35-40 original % 35-40 size 0.3
****** VESICLES *****
Type: vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 20
replacement: Interstices
comments : Brownish green
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0007
hole: 642E top int: 091 cm observer code: LEH
core: 013R pieces: 013
rock name: Moderately plagioclase phyric basalt
texture: Intersertal
where sampled: Flow 7
***** PHENOCRYSTS *****
Plagioclase present % ~10 original % ~10 size 0.5-2.0
morphology : Prismatic
comments : Agglomerated, fractured and filled with
smectite.
***** GROUNDMASS *****
Plagioclase present % ~50 original % ~50 size <0.1
****** VESICLES *****
Type: Vesicles %: 1-2
filling : Smectite
shape : Round to subrounded
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10-12
replacement:
comments : Yellowish green in interstices and
possibly small percent replacing olivine.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0007
hole: 642E top int: 038 cm observer code: LEH
core: 014R pieces: 007
rock name: Highly plagioclase phyric basalt
texture: Intersertal
where sampled: Flow 7
***** PHENOCRYSTS *****
Plagioclase present % 12-15 original %12-15 size 0.5-2.0
morphology : Prismatic
comments : Glomerophyric; some cored with previous
plagioclasegeneration and clinopyroxene.
***** GROUNDMASS *****
Plagioclase present % 35 original % 35 size 0.05-0.13
****** VESICLES *****
Type: Vesicles %: <1
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 20-25
replacement: Interstices
comments : Replaces groundmass, cracks in
phenocrysts.
****** OVERALL COMMENTS ******
Several radial aggregates of plagioclase laths, at least one with olivine
(iddingsite) at center.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0008
hole: 642E top int: 128 cm observer code: LEH
core: 014R pieces: 019
rock name: Highly plagioclase phyric basalt
texture: Intersertal, aphanitic
where sampled: Flow 8
***** PHENOCRYSTS *****
Plagioclase present % 10-12 original %10-12 size 0.5-2.0
morphology : Prismatic, skeletal
comments : Partially altered, zoned, glomerophyric; some
withclinopyroxene cores.
***** GROUNDMASS *****
Plagioclase present % 25 original % 25 size 0.1-0.2
****** VESICLES *****
Type: Vesicles %: N/A
filling : Calcite/smectite
shape : Round
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 25-30
replacement: Interstices, all minerals
comments : Medium green smectite.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0010
hole: 642E top int: 073 cm observer code: LEH
core: 015R pieces: 009
rock name: Aphyric basalt
texture: Subophitic, aphyric
where sampled: Flow 10
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Size measured along length.
Plagioclase present % 35 original % 35 size 0.4-0.5
****** VESICLES *****
Type: Vesicles %: 4-5
filling : Rimmed with smectite
shape : Ovoid
Precent of rock estimated separate from rims.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 15
replacement: Interstitial
comments :
****** OVERALL COMMENTS ******
Olivine tholeiite. Thin section nearly completely destroyed during polisihing;
olivine "crystals" (relict) especially affected.
ODP hard-rock thin section description - verbose form
leg : 104 section: 04 unit/subunit : 0011
hole: 642E top int: 103 cm observer code: LUV
core: 015R pieces: 007
rock name: Sparsely plagioclase phyric basalt
texture: Subophitic to intergranular
where sampled: Flow 11
***** PHENOCRYSTS *****
Plagioclase present % 1-2 original % 1-2 size 1.5
composition: An60
morphology : Short laths, stubby
comments : Euhedral, embayed zoned, multiple zones up to
An80.
***** GROUNDMASS *****
Completely altered to iddinsite.
Olivine present % 5 original % 5 size 0.15
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10
replacement: Intergranular
comments : Green-brown radiating fibers.
****** OVERALL COMMENTS ******
30% of the slide is plucked. Probably piece number 7.
ODP hard-rock thin section description - verbose form
leg : 104 section: 05 unit/subunit : 0013
hole: 642E top int: 009 cm observer code: LUV
core: 015R pieces: 001
rock name: Sparsely plagioclase phyric basalt
texture: Subophitic, intergranular
where sampled: Flow 13
***** PHENOCRYSTS *****
Plagioclase present % 1-2 original % 1-2 size 1-1.5
composition: An54
morphology : N/A
***** GROUNDMASS *****
Plagioclase present % 45 original % 45 size 0.2-0.4
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10
replacement: Intergranular
comments : Fibrous, green-brown.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 05 unit/subunit : 0012
hole: 642E top int: 105 cm observer code: LUV
core: 015R pieces: 009
rock name: Sparsely plagioclase phyric basalt
texture: Subophitic to intergranular
where sampled: Flow 12
***** PHENOCRYSTS *****
Plagioclase present % 4 original % 4 size 1.5
composition: An60
morphology : Subhedral
comments : Laths, glomerophyric.
***** GROUNDMASS *****
Plagioclase present % 50 original % 50 size 0.3
****** VESICLES *****
Type: Vesicles %: 10
shape : Subround
Carbonate centers, smectite rims.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10
replacement: Intergranular
comments : Also altering olivine.
****** OVERALL COMMENTS ******
Carbonate in vesicles radiates from a single point. Probably piece number 9B.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0015
hole: 642E top int: 022 cm observer code: LUV
core: 016R pieces: 003
rock name: Medium grained mixed basalt
where sampled: Flow 15, mixed flow top
***** PHENOCRYSTS *****
Plagioclase present % 40 original % 40 size 0.2
composition: An52
morphology : Laths
comments : Intergranular and intersertal.
***** GROUNDMASS *****
Very thin laths or columns.
Plagioclase present % 35 original % 35 size 0.3
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: percent:
replacement:
comments :
****** OVERALL COMMENTS ******
Domains of medium grained separated by fine grained or quenched material. Sharp
boundary between fine and medium grained material. Probably piece number 3.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0015
hole: 642E top int: 032 cm observer code: LUV
core: 016R pieces: 004
rock name: Medium grained basalt
where sampled: Flow 15, mixed flow top
***** PHENOCRYSTS *****
Olivine present % 5 original % 5 size 0.3
morphology : N/A
comments : Iddingsitized.
***** GROUNDMASS *****
Plagioclase present % 45 original % 45 size 0.1-0.4
****** VESICLES *****
Type: Vesicles %: 15
filling : Dark green clay
shape : Irregular
Intergranular.
****** SECONDARY MINERALIZATION ******
mineral name: percent:
replacement:
comments :
****** OVERALL COMMENTS ******
Domain of medium grained separated by fine grained material, sharp boundaries
between them.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0017
hole: 642E top int: 104 cm observer code: PAR
core: 017R pieces: 019
rock name: Red-weathered aphyric basalt
texture: Weak pilotaxitic
where sampled: Flow 17, weathered top, 1m below top.
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Iddingsitized throughout-red-brown, completely iddingsitized cores of olivine may
hold calcite.
Olivine present % 20 original % 20 size 0.05-0.2
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: ~5
replacement: Plagioclase
comments : Green smectite: first phase vein fill
smectite.
****** OVERALL COMMENTS ******
Probably piece number 19.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0017
hole: 642E top int: 104 cm observer code: PAR
core: 017R pieces: 015
rock name: Weakly reddened basalt
texture: Weak trachytic
where sampled: Flow 17, 2.6 m below recovered flow top.
***** PHENOCRYSTS *****
Plagioclase present % 1-2 original % 1-2 size .8-.4
composition: An65
morphology : N/A
comments : Zoned (An55 on outer rim).
***** GROUNDMASS *****
Some euhedral and anhedral. Iddingsite pseudomorphs.
Olivine present % 15 original % 15 size 0.1-0.5
****** VESICLES *****
Type: Vesicles %: 7
filling : Unfilled
shape : Round
Narrow, oxide staining around vesicle.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 7-10
replacement: Plagioclase and margins
comments : To olivine/green smectite.
****** OVERALL COMMENTS ******
3-5mm xenolith of basalt identified within thin section. Black, dusty margin to
finer grained groundmass with moderate to strong pilotaxitic texture.
ODP hard-rock thin section description - verbose form
leg : 104 section: 03 unit/subunit : 0017
hole: 642E top int: 070 cm observer code: PAR
core: 017R pieces: 006
rock name: Aphyric tholeiitic basalt
where sampled: Flow 17, 3.7m below recovered flow top.
***** PHENOCRYSTS *****
Plagioclase present % <1 original % <1 size 2-5
composition: An60
morphology : Euhedral tabules
comments : Center margin normally zoned, locally
glomerophyric.
***** GROUNDMASS *****
All smectite or iddingsite in alteration zones.
Olivine present % 15 original % 15 size 0.1-0.3
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: <3
replacement: (?) Cavities and margins
comments : Yellow brown smectite, radiofibrous.
****** OVERALL COMMENTS ******
Patchy, smectite-rich alteration zones, plagioclase (locally replaced 80% by
green smectite), altered olivines are iddingsite-rich, c.f. to smectite-rich
outside zones. Plagioclase is relatively fresh. Open fracture cutting section has
altered margins.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0017
hole: 642E top int: 027 cm observer code: PAR
core: 018R pieces: 011
rock name: Streaky aphyric basalt
texture: Locally trachytic
where sampled: Flow 17, 5.4 m below recovered flow top.
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Iddingsite margins, smectite cores. Cleanest alteration textures in olivines in
alteration zones.
Olivine present % 12 original % 12 size 0.1-0.6
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: N/A
replacement: Plagioclase (+ cpx?)
comments : Green smectite to maximum of 65% of
discrete alteration zones (streaky
laminations(?)). Zones make up 10% of
rock, about 1mm wide, discontinuous,
approximately parallel or patchy.
****** OVERALL COMMENTS ******
Clearest alteration textures in olivines in alteration zones. Preferred
orientation of plagioclase groundmass only locally subparallel to alteration
streaking.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0017
hole: 642E top int: 027 cm observer code: PAR
core: 018R pieces: 011
rock name: Streaky tholeiitic basalt
texture: Subophitic/trachytic
where sampled: Flow 17, 6.7 m below recovered flow top.
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Moderate trachytic/pilotaxitic, deflection into alteration fabric.
Plagioclase present % 50 original % 50 size 0.2-0.65
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: N/A
replacement: Interstices and locally plagioclase
comments : In alteration streaks/bands. Within
alteration bands rock is up to 45%
smectite, 1.0+ mm wide discontinuous,
locally diffuse.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 03 unit/subunit : 0017
hole: 642E top int: 072 cm observer code: PAR
core: 018R pieces: 001
rock name: Aphyric tholeiitic basalt
texture: Trachytic/pilotaxitic glomerophyric
where sampled: Flow 17, 8.5 m below recovered flow top.
***** PHENOCRYSTS *****
Palgioclase present % <2 original % <2 size 0.1
composition: An65
morphology : Subhedral
comments : Locally glomerophyric.
***** GROUNDMASS *****
Iddingsite within alteration fabric and smectite replaces olivine outside
alteration fabric, little iddingsite.
Olivine present % 12 original % 12 size 0.1-0.35
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: N/A
replacement: Plagioclase
comments : Strongly altered in alteration "streak"
zones.
****** OVERALL COMMENTS ******
Poor alteration fabric, patches and single streak.
ODP hard-rock thin section description - verbose form
leg : 104 section: 04 unit/subunit : 0017
hole: 642E top int: 037 cm observer code: PAR
core: 018R pieces: 002
rock name: Aphyric tholeiitic basalt
texture: Trachytic/pilotaxitic
where sampled: Flow 17, flow interior
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Smectite and iddingsite replacement. Iddingsite only within alteration zones.
Olivine present % 12 original % 12 size 0.1-1.0
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: N/A
replacement: Interstitial and plagioclase
comments : In alteration zones, green smectite.
****** OVERALL COMMENTS ******
Alteration zones are well developed, about 1 mm wide, green smectite rich, with
good alignment of feldspar laths within zones. Probalbly piece number 2.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0018
hole: 642E top int: 042 cm observer code: LEH
core: 019R pieces: 004
rock name: Sparsely phyric tholeiitic basalt
texture: Glomerophyric
where sampled: Flow 18, 0.6 m below recovered flow top.
***** PHENOCRYSTS *****
Plagioclase present % 2 original % 2 size 1-2
composition: An65
morphology : Tabular and laths
comments : Normally zoned, locally glomerophyric
***** GROUNDMASS *****
Iddingsitized, rims mostly smectite psuedomorphs.
Olivine present % 12 original % 12 size 0.1-0.4
****** VESICLES *****
Type: Vesicles %: 7
filling : Smectite calcite cores
shape : Irregular
Radio-fibrous green smectite fill, yellow smectite rims.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 3
replacement: Interstitial and plagioclase
comments : Smectite patches.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0018
hole: 642E top int: 099 cm observer code: LEH
core: 019R pieces: 003
rock name: Tholeiite basalt
texture: Intersertal to subophitic
where sampled: Flow 18
***** PHENOCRYSTS *****
Plagioclase present % 1 original % 1 size 0.5-1.0
morphology : Prismatic
comments : Glomerophyric, zoned.
***** GROUNDMASS *****
Width is <0.05 mm.
Plagioclase present % ~40 original % ~40 size 0.2-0.6
****** VESICLES *****
Type: Vesicles %: N/A
shape : Ovoid
Filled with smectite and isotropic mineral.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10
replacement: Interstices and vesicles
comments :
****** OVERALL COMMENTS ******
Maybe two clinopyroxenes: 1) Augite with ~Ti (purplish color). 2) Pigeonite (very
pale to colorless; 2V; lower extinction angle).
ODP hard-rock thin section description - verbose form
leg : 104 section: 04 unit/subunit : 0018
hole: 642E top int: 009 cm observer code: PAR
core: 019R pieces: 001
rock name: Sparsely phyric tholeiitic basalt
texture: Subophitic
where sampled: Flow 18, 5.2 m below recovered flow top.
***** PHENOCRYSTS *****
Plagioclase present % >1 original % >1 size 0.1-1.2
composition: AN60
morphology : Tabular and laths
comments : Fresh, most normally zoned, few oscillatory.
***** GROUNDMASS *****
Iddingsitized and smectite replaced.
Olivine present % 10 original % 10 size 0.1-0.5
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 5
replacement:
comments : Green smectite rich alteration patches.
****** OVERALL COMMENTS ******
Probably piece number 1A.
ODP hard-rock thin section description - verbose form
leg : 104 section: 03 unit/subunit : 0029
hole: 642E top int: 015 cm observer code: LEH
core: 027R pieces: 014
rock name: Plagioclase-phyric tholeiitic basalt
texture: Hyalocrystalline or trachylitic
where sampled: Flow 29
***** PHENOCRYSTS *****
Plagioclase present % 1 original % 1 size 0.5-2.5
morphology : Prismatic
comments : Glomerophyric, fractured, partially altered.
***** GROUNDMASS *****
Opaque, "isotropic", cryptocrystalline.
Tachylite present % 40 original % 40 size N/A
****** VESICLES *****
Type: Vesicles %: Lots
filling : Smectite, zeolite
shape : Irregular
Some with center voids.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 12-15
replacement: Fractures in plagioclase phenocrysts
comments : Also altering large plagioclase,
interstitial.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 04 unit/subunit : 0029
hole: 642E top int: 066 cm observer code: DIV
core: 027R pieces: 008
rock name: Lehgioclase-phyric basalt
texture: Intersertal
where sampled: Flow 29
***** PHENOCRYSTS *****
Plagioclase present % 10-12 original %10-12 size 1.0-2.5
morphology : Prismatic
comments : Tend to be fractured and/or embayed.
***** GROUNDMASS *****
Occasional laths up to 0.7 mm.
Plagioclase present % 35 original % 35 size 0.05-0.2
****** VESICLES *****
Type: Vesicles %: 5
filling : Smectite
shape : Round
Not counted in mineral totals.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 15
replacement: Interstitial
comments : Uniform brown.
****** OVERALL COMMENTS ******
Plagioclase laths radiate from (altered) olivine. Opaques and (altered) olivine
are often concentrated in linear bands and around vesicle rims.
ODP hard-rock thin section description - verbose form
leg : 104 section: 05 unit/subunit : 0029
hole: 642E top int: 011 cm observer code: LEH
core: 027R pieces: 001
rock name: Plagioclase-clinopyroxene phyric basalt
texture: Intersertal to subophitic
where sampled: Flow 29
***** PHENOCRYSTS *****
Plagioclase present % 12 original % 12 size 1-2
morphology : Prismatic
comments : Glomerophyric, subophitic.
***** GROUNDMASS *****
Size: 0.05-0.6 length, ~0.5 width.
Plagioclase present % 45 original % 45 size 0.05-0.6
****** VESICLES *****
Type: Vesicles %: 15
filling : Smectite and zeolite
shape : Elongate, irregular
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 3-5
replacement: Interstices
comments : Medium brown.
****** OVERALL COMMENTS ******
Minerals are quite fresh.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0074
hole: 642E top int: 121 cm observer code: LEH
core: 067R pieces: 026
rock name: Altered aphyric basalt
texture: (?) hyalocrystalline to intersertal
where sampled: Flow 74
grain size: Medium
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Prismatic crystalls tend to be more altered.
Plagioclase present % 20 original % 20 size 0.2-2.0
****** VESICLES *****
Type: Vesicles %: 15
filling : Smectite and zeolite
shape : Rounded to irregular
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 10
replacement: Interstices
comments : Light green smectite, well crystallized.
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0074
hole: 642E top int: 052 cm observer code: LEH
core: 067R pieces: 012
rock name: Aphyric tholeiitic basalt
texture: Intersertal
where sampled: Flow 74
grain size: Medium
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Plagioclase present % 40 original % 40 size 0.05-1.5
****** VESICLES *****
Type: Vesicles %: 15
filling : Smectite
shape : Round
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 30
replacement: Interstices
comments : Light greenish brown.
****** OVERALL COMMENTS ******
Magnetite, nice skeletal structures, polishing scratches observable in reflected
light under XP, also hematite.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0106
hole: 642E top int: 054 cm observer code: LEH
core: 097R pieces: 017
rock name: Throughly altered flow
texture: Quenched
where sampled: Flow 106
***** PHENOCRYSTS *****
Plagioclase present % 2 original % 2 size <0.1
morphology : Prismatic
***** GROUNDMASS *****
Quenched. Skeletons of incipient crystals, quenched, altered.
Plagioclase present % 7 original % 7 size N/A
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 90
replacement: All
comments : Cryptocrystalline.
****** OVERALL COMMENTS ******
Thin section has been almost completely wiped during processing, possible relict
perlitic structures.
ODP hard-rock thin section description - verbose form
leg : 104 section: 01 unit/subunit : 0109
hole: 642E top int: 106 cm observer code: LEH
core: 098R pieces: 014
rock name: Altered quenched flow
texture: Quenched, altered
where sampled: Flow 109
***** PHENOCRYSTS *****
Plagioclase present % 1 original % 1 size 0.1-1.2
morphology : Prismatic
comments : Mildly to severely altered.
***** GROUNDMASS *****
Quenched, altered percentage is for distinguishable plagioclase.
Plagioclase present % 10 original % 10 size N/A
****** VESICLES *****
Type: Vesicles %: 20
Smectite-analcite-mordenite-adularia, in from rims.
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 90
replacement: All
comments : Quenched textures preserved.
****** OVERALL COMMENTS ******
Alteration assemblage typical of 100 - 150 degree C fluid.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0109
hole: 642E top int: 062 cm observer code: LEH
core: 098R pieces: 013
rock name: Perlite (glassy flow)
texture: Perlitic
where sampled: Flow 109
***** PHENOCRYSTS *****
Plagioclase present % 2 original % 2 size 0.2-1.3
morphology : Prismatic
comments : Tends toward glomerophyric.
***** GROUNDMASS *****
Altered to perlite, light purplish brown.
Glass present % 98 original % 98 size N/A
****** VESICLES *****
Type: Vesicles %: 5
filling : Smectite and zeolite
shape : Round
Also includes fractures.
****** SECONDARY MINERALIZATION ******
mineral name: percent:
replacement:
comments :
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 03 unit/subunit : 0112
hole: 642E top int: 013 cm observer code: LEH
core: 099R pieces: 001
rock name: Altered quenched flow
texture: Quenched
where sampled: Flow 112
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Quenched.
Plagioclase present % 15 original % 15 size N/A
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 70
replacement: All
comments : Light greenish brown and brown
smectites(?).
****** OVERALL COMMENTS ******
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0115
hole: 642E top int: 026 cm observer code: LEH
core: 102R pieces: 007
rock name: Hydrothermally leached glassy flow
texture: Bleached
where sampled: Flow 115
***** PHENOCRYSTS *****
Plagioclase present % 3-5 original % 3-5 size 0.1-1.5
morphology : Prismatic
comments : Glomerophyric.
***** GROUNDMASS *****
Replaced (reflected light).
Pyrite present % <<1 original % <<1 size N/A
****** VESICLES *****
Type: Vesicles %: N/A
filling : None
shape : Round
****** SECONDARY MINERALIZATION ******
mineral name: Clays percent: 95
replacement: All minerals
comments : Cryptocrystalline.
****** OVERALL COMMENTS ******
Rock has been leached white.
ODP hard-rock thin section description - verbose form
leg : 104 section: 02 unit/subunit : 0006
hole: 642E top int: 124 cm observer code: LEH
core: 107R pieces: 011
rock name: Shallow level basalt dike
texture: Hyalocrystalline
where sampled: Dike 6
***** PHENOCRYSTS *****
***** GROUNDMASS *****
Tachylite? and pyrite.
Opaques present % 40 original % 40 size N/A
****** VESICLES *****
Type: Vesicles %: 0
****** SECONDARY MINERALIZATION ******
mineral name: Clays(?) percent: 10
replacement: Interstices
comments : May be incipient crystallization
structures?
****** OVERALL COMMENTS ******
Grain size of plagioclase increases, amount of glass increases, pyrite increases
near vein-like structure; no apparent increase in alteration.
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These Web pages are from the Core Data from the Ocean Drilling Program Legs 101-129 CD-ROM produced in 2001 by the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Environmental Satellite, Data, and Information Service, National Geophysical Data Center, and collocated World Data Center for Marine Geology and Geophysics, Boulder. Data were compiled in cooperation with the U.S. Science Support Program, the Joint Oceanographic Institutions, Inc., and the U.S. National Science Foundation. Please see the NGDC privacy, disclaimer, and copyright notices. Additional ocean drilling data are available from NGDC and from the ODP/IODP.
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