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TRANSCRIPT
SITE 867 HOLE
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10YR8/2
CORED 0.0-10.0 mbsf
Description
FLOATSTONE
Major Lithology:FLOATSTONE, white (10YR 8/2), withpartially recrystallized micrite, coatedgrains, bivalve fragments (Gervillia ?and probable caprinid rudist),gastropods, lithoclasts, red algae, voidsfilled with sparry calcite. Someencrustation of larger shell fragments,algal fragments.
Minor Lithologies:BOUNDSTONE, as a clast withLithophaga and sponge borings.
867A-1M! 1
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SITE 867 HOLE B CORE 1R CORED 0.0-8.1 mbsf
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10YR8/2To
10YR8/3
Description
FLOATSTONE, WACKESTONE,GRAINSTONE, RUDSTONE,PACKSTONE, andFORAMINIFER-NANNOFOSSIL CHALK
Major Lithologies:FORAMINIFER-NANNOFOSSIL CHALKphosphatized, yellowish-brown (10YR5/4), locally conglomeratic, withmm-scale rounded clasts, andimpregnated with black (10YR 2/1)manganese dendrites, which restsdirectly on FLOATSTONE in Section 1,0-29 cm. FLOATSTONE, white to verypale brown (10YR 8/2 to 10YR 8/3),contains well-rounded intraclasts ofMUDSTONE and abundant rudist debris,occasional gastropods, corals andgreen algae, set in a matrix of peloidalmicrite. This lithology occurs in Section1, 0-136 cm, Section 2, 0-14 cm and43-92 cm and Section 3, 61-93 cm,where it contains sparse cm-scaleoncoids. Local void spaces are filledwith sparry calcite and impregnated withmanganese dendrites, these latterbeing particularly common in Section 1.Section 1 has local intercalations ofWACKESTONE. Section 2, 14-43 cmcontains peloidal PACKSTONE, white(10YR 8/2) with many oyster and rudistfragments and corals. Section 2,92-118 cm comprises WACKESTONE,peloidal, with shell fragments, rudistsand corals, blackened intraclasts, largevugs, an obvious burrow and isphosphatized. Section 2, 118-150 cmand Section 3, 0-38 cm are composedof RUDSTONE with imbricated clasts ofrudist and gastropod fragments,commonly with micrite envelopes,peloids, and thin crusts. Section 3,38-61 cm is a very pale brown (10YR8/3) GRAINSTONE-RUDSTONE thatcontains local keystone vugs.
867B-1R 1
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SITE 867 HOLE B CORE 2R CORED 8.1 - 15.1 mbsf 867B-2R! I 1
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Structure
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10YR8/2To
10YR5/1
10YR8/2
Description
WACKESTONE , PACKSTONE,MUDSTONE, and FLOATSTONE
Major Lithologies:Section 1, 0-20 cm containsWACKESTONE-PACKSTONE, verypale brown (10YR 8/4), phosphatized,locally laminated with abundant shellfragments and peloids, some of whichare blackened, and dark specks of Mnoxyhydroxides and rare bird's-eyevugs. Section 1, 20-50cm, containsFLOATSTONE, white to gray (10YR8/1 to 10YR 5/1), graded, withblackened lithoclasts (up to cm-scale)and blackened shell fragments,including rudist debris. MUDSTONE,dark yellowish brown (10YR 4/6),pervasively phosphatized occurs inSection 1, 50-64 cm. Section 1,64-113 cm contains WACKESTONE,white (10YR 8/1) with dasycladaceanalgae, gastropods, bivalve fragmentsand black pebbles. Miliolids areabundant between 96-113 cm.Section 1, 113-120 cm comprisesPACKSTONE to WACKESTONE,yellow (10YR 7/6) with peloids,intraclasts, shell fragments, andMn-dendrites, which are locallypink-stained (5YR 4/8). MUDSTONEto WACKESTONE, white (10YR 8/1),with gastropods and bivalve shells inSection 1, 120-138 cm contains lightgray (5Y 7/2) sediment of similarcomposition, brecciated burrow fills,some black pebbles and minordolomitization. In Section 1, 138-150cm, PACKSTONE, very pale brown(10YR 8/3), peloidal, laminated, withbird's-eyes grades up into a shell hashwith large molds of rudists that havean irregular contact with the overlyingfacies. Section 2 is composed ofWACKESTONE, white (10YR 8/2) tolight brownish gray (2.5Y 6/2), heavilybioturbated, irregularly colored andbrecciated with dissolved shellfragments, angular black pebbles upto 1 cm in diameter and local peloids.In Section 2, 7-14 cm, there are somedisrupted fragments of algal-mat and ?calcite pseudomorphs after gypsum.
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SITE 867 HOLE B CORE 3R CORED 15.1-18.1 mbsf
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10YR8/2To
10YR8/3
Description
MUDSTONE, WACKESTONE,RUDSTONE, and FLOATSTONE
Major Lithologies:WACKESTONE, very pale brown
fragments and gastropods. Interval0-22 cm contains angular blackpebbles, is brecciated and includesinternal cavities filled with laminatedsediment, some of which isphosphatized. Interval 22-40 cmcomprisesWACKESTONE-MUDSTONE, white(10YR 8/1), with peloids. Interval40-65 cm, is a brown (1OYR 6/3),phosphatized WACKESTONE, some ofwhich is a cavity fill. Interval 65-78 cmis constituted by RUDSTONE, verypale brown (10YR 8/4), containingrudist fragments and somegastropods. Interval 78-122 cm is aFLOATSTONE, very pale brown (10YR8/3), with abundant shell fragments,intraclasts of cm-scale, someblackened and with much vuggyporosity, a portion of which is occludedby mm-laminated cavity fills.Intervals, 78-79 cm and 116-121 cmcontain such cavity fills and areassociated with phosphatization.
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SITE 867 HOLE B CORE 4R CORED 18.1 -24.5 mbsf
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10YR7/1
10YR8/2To
10YR8/3
10YR8/1
10YR8/3
Description
PACKSTONE, GRAINSTONE,RUDSTONE, WACKESTONE, andMUDSTONE
Major Lithologies:Section 1, 0-63 cm is PACKSTONE,light gray (10YR 7/1), with bivalve andgastropod fragments. Blacklithoclasts occur throughout thisinterval. Section 1, 63 cm to Section 2,70 cm is GRAINSTONE andRUDSTONE, white (10YR 8/2) to verypale brown (10YR 8/3), peloidal, withmany large mollusc fragments, rarecoral, some keystone vugs. Section 2,70-150 cm is bioturbatedWACKESTONE with some cm-sizeupright oriented bivalves. Section 3,0-150 cm is GRAINSTONE, white(10YR 8/1), peloidal, with largebivalve-fragments and molds, rarecoral fragments. Small blackenedlithoclasts occur throughout. Someburrowing occurs; burrows are filledwith white (N9) mud. Section 4 isfossiliferous MUDSTONE, very palebrown (10YR 8/3) with small molluscfragments and molds. Cm-scalecavities with speleothem deposits anddog-tooth spar cement occur inSection 1, 123-129 cm and in Section2, 21-26 cm. All the material iswell-cemented, the coarser-grainedintervals contain abundant moldic andsome vuggy porosity.
Minor Lithology:Section 1, 0-30 cm contains smallclasts of PHOSPHORITE. A horizon oflaminated PHOSPHORITE cavity-filloccurs in Section 1, 19-23 cm.
SITE 867 HOLE B CORE 5R CORED 24.5-33.9 mbsf
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10YR8/1
Description
WACKESTONE
Major Lithology:0-32 cm: WACKESTONE, white (10YR8/1). Abundant moldic porosity ofhigh-spired gastropods andthin-shelled bivalves occursthroughout.
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SITE 867 HOLE B CORE 6R CORED 33.9-43.2 mbsf
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10YR8/2
Description
GRAINSTONE
Major Lithology:
0-73 cm: GRAINSTONE, white (10YR8/2), peloidal, with some small bivalveshell fragments. From 0-47 cm, thematerial is very well sorted. From 47-73cm, sorting is moderate.
Minor Lithology:WACKESTONE, white (10YR 8/2), withgastropod and bivalve fragments,occurs from 67-73 cm. One pebblecontains a chunk of recrystallizedcoral.
SITE 867 HOLE B CORE 7R CORED 43.2-52.5 mbsf
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10YR8/1
Albian
Description
WACKESTONE and GRAINSTONE
Major Lithologies:0-20 cm: WACKESTONE, white (10YR8/1) with moldic porosity of gastropods.20-47 cm: GRAINSTONE, white (10YR8/1), with moldic porosity. Fragments ofrudists occur at 45-47 cm. The materialis well indurated. Molds are lined withdog-tooth spar cement. Black pebbleintraclasts occur at 15 cm; 35 cm and40 cm.
867B-6R 1 867B-7R I 1
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SITE 867 HOLE B CORE 8R CORED 52.5-61.8 mbsf 867B-8RJ I 1
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10YR8/2To
10YR8/3
Description
MUDSTONE, WACKESTONE,FLOATSTONE, and RUDSTONE
Major Lithology:Section 1,0-6 cm containsMUDSTONE-WACKESTONE, white(10YR 8/1), with gastropods. In Section6-44 cm, white to very pale brown(10YR8/2to10YR8/3),WACKESTONE-FLOATSTONE, withrudist (caprinids) fragments and smallgastropods. In Section 1, 44 cm toSection 2, 6 cm,RUDSTONE-FLOATSTONE, white tovery pale brown (1 OYR 8/2 to 10YR8/3), with cm-scale cavities, some ofwhich is filled with white (1 OYR 8/1)MUDSTONE. Section 2, 6-53 cmcontains WACKESTONE, white to verypale brown (10YR 8/2 to 10YR 8/3), withblackened angular granules, rudistshells with white micritic fringes andsmall gastropods. In Section 2, 53-60cm, MUDSTONE-WACKSTONE, whiteto very pale brown (1 OYR 8/2 to 10YR8/3), with benthic foraminifers (rare)and burrows (?) infilled with light gray(10YR 7/1) MUDSTONE.
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SITE 867 HOLE B CORE 9R CORED 61.8-66.4 mbsf 867B-9R . 1
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10YR8/2
10YR8/1
Description
WACKESTONE andFLOATSTON E- R U DSTON E
Major Lithologies:WACKESTONE, Section 1, 0-150 cm,white (10YR 8/2) with light-colored (5YR8/2) and very pale brown (10YR 8/3)patches, and a mottled appearance,resulting from bioturbation or
water-escape features. ThisWACKESTONE contains abundant darkgray (1OYR 4/1) intraclasts ofMUDSTONE, numerous thin bivalveshells, and gastropods with moldicporosity. Section 1, 56-63 cm exhibitsan example of vadose-zone cement,which has a slope of 4 degrees. Aspeleothem exists at the vadosephreatic boundary.FLOATSTONE-RUDSTONE, white(1 OYR 8/1) with abundant mollusc andbivalve debris comprises Section 2.Moldic porosity developed around theoriginal aragonitic shell fragments,many of which contain bored cavitieswith MUDSTONE fills. MUDSTONE isalso present as a veneer on some of thelarge bioclasts.
SITE 867 HOLE B CORE 10R CORED 66.4-68.4 mbsf
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10YR8/1
10YR8/2
Description
PACKSTONE and MUDSTONE
Major Lithologies:PACKSTONE, white (10YR 8/1), withabundant shell debris, dark grayintraclasts, internal molds of borings,and moldic porosity produced bydissolution of gastropod shells. The17-19 cm interval consists of coral.MUDSTONE (in 93-150 cm), white,(10YR 8/2) contains sparse faunaincluding bivalves, dasycladaceanalgae, and benthic foraminifers.
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SITE 867 HOLE B CORE 11R CORED 68.4-71.4 mbsf 867B-11R
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10YR8/2To
10YR8/3
Description
WACKESTONE and MUDSTONE
Major Lithology:WACKESTONE (0-49 cm), white to very
pale brown (1 OYR 8/2 to 10YR 8/3), withnumerous dark gray (10YR 4/1)intraclasts, gastropods (as molds), andbenthic foraminifers (miliolids). Manysmall thin-shelled bivalves. The interval49-96 cm contains MUDSTONE, verypale brown (10YR 8/3) with very smallbioclasts and benthic foraminifers(miliolids).
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10YR8/2
CORED 71.4-75.3 mbsf
Description
MUDSTONE, WACKESTONE, andPACKSTONE
Major Lithology:
Section 1, 0-22 cm containsMUDSTONE, white (10YR 8/2), with afew small high-spired gastropod moldsand granule- to small pebble-sizedintraclasts. Small boring cavities (< 1mm in diam.) occur. Section 1, 22 cm toSection 2, 33 cm containsWACKESTONE, white (10YR 8/2), withbivalve (including rudist) and gastropodshell fragments and blackened (darkgray, 10YR 4/1) intraclasts.Occasional horizon rich in gastropod
molds occur. I ne interval section i ,40-142 cm includes cavities, some ofwhich are infilled with one to severalcalcite layers. Speleothem in Section2, 25 cm. MUDSTONE (Section 2,33-100 cm), white (10YR 8/2),burrowed, with moldic porosity pfgastropods and dasycladacean algae.Section 2, 100-138 cm containsWACKESTONE- PACKSTONE, white(10YR 8/2), with predominately bivalvefragments, some dasycladaceanalgae, and a few dark gray intraclasts.Section 3, 0-80 cm, containsWACKESTONE, white (10YR 8/2), withnumerous bivalve shell fragments,molds of gastropods anddasycladacean algae, and dark grayintraclasts. Molds infilled with sparrycalcite. Possible cave floor (phreaticzone) layers in Section 3, 27-30 cm.
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SITE 867 HOLE B CORE 13R CORED 75.3-76.8 mbsf 867B-13R
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10YR8/2
Description
MUDSTONE and WACKESTONE
Major Lithology:WACKESTONE (0-59 cm), white (10YR8/2), with abundant bivalve and rudistfragments, moldic porosity of gastropodfragments infilled with sparry calcite andcoral (20-23 cm). Some speleothemfillings indicate vadose zones.MUDSTONE (59-89 cm), white (10YR8/2), with moldic porosity of gastropodshells and speleothem filling. Theinterval 89-150 cm containsWACKESTONE, white (10YR 8/2), withdark gray intraclasts and rudistfragments and fining up overapproximate 1 m.
SITE 867 HOLE B CORE 14B CORED 76.8-76.8 mbsf
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2.5YN8/0
Description
WACKESTONE-PACKSTONE
Major Lithology:WACKESTONE-PACKSTONE, white(2.5 Y 8/0), with numerous bivalveclasts and angular black pebbles. Minorvuggy porosity is partially filled withinternal sediment and coarse calcitespar.
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SITE 868 HOLE A CORE 1R CORED 0.0-8.0 mbsf
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GRAINSTONE-RUDSTONE,MUDSTONE,PACKSTONE-GRAINSTONE, andFLOATSTONE
Major Lithologies:Section 1, 0 cm to Section 2, 27 cmcontains GRAINSTONE-RUDSTONE,white (10YR 8/2) composed almostentirely of rudist debris. Some localFLOATSTONE is present andcontains gastropods, calcareousalgae, oncoids, and micritized peloids.Keystone vugs occur in Section 1,107-113 cm and 137-145 cm. InSection 2, 27-51 cm, there is aninterval of MUDSTONE containingsmall gastropods and ostracods, aswell as an internal cavity, filled withslightly darker sediment. Section 2,51-62 cm containsPACKSTONE-GRAINSTONE withsome partially filled cavities: Section2, 62-70 cm comprises MUDSTONEwith black pebbles, partly red-stainedand containing cavities filled withbanded red (10R 6/6) and white (10YR8/2) MUDSTONE. In Section 2, 65-68cm, there is speleothem developmentin the top of a cavity with a laminatedcrust in the base of void.
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SITE 868 HOLE A CORE 2R CORED 8.0-11.1 mbsf 868A-2R 1
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N9To
10YR8/2
Description
WACKESTONE-PACKSTONE,FLOATSTONE, and BOUNDSTONE
Major Lithologies:Discrete beds ofWACKESTONE-PACKSTONE andFLOATSTONE, white (N9-10YR 8/2),with cm-scale fragments of rudistbivalves. Large caprinid shells occur inseveral places. Sclerosponge
BOUNDSTONE intervals occur inSection 1, 47-53 cm and 77-90 cm, andin Section 2, 7-23 cm. Section 1, 55-75cm contains abundant cm-scalerequeinid rudist shells. Moldic andvuggy porosity are common throughout.
Minor Lithology:Section 2, 62-70 cm comprisesMUDSTONE, white (10YR 8/1), whichforms 1-2 cm size rounded structuresseparated by vuggy granularboundaries. These may beburrow-structures.
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SITE 868 HOLE A CORE 3R CORED 11.1-13.6 mbsf
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10YR8/2To
5YR 7/3
2.5YR6/4To
2.5YR5/6
10YR6/6
10YR8/2
Description
FLOATSTONE, PACKSTONE, andWACKESTONE
Major Lithology:Section 1, 0-38 cm containsPACKSTONE-FLOATSTONE, white(10YR 8/2), with abundant rudist(caprinid) shells which have whitemicritic fringes and small mm-scalecavities with dog's tooth calcite. InSection 1, 38-47 cm, PACKSTONE,pink (5YR 7/3) with small angular bivalveshell fragments. Near the base of thisinterval is a cavity filled with grayishgreen MUDSTONE, with white calciticlining. Section 1, 47-110 cm containsFLOATSTONE, light reddish brown(2.5YR 6/4 ) grading to red (2.5YR 5/6),with large caprinid shells. In the upperpart of this horizon, these shells aredissolved and filled with several layersof pink to reddish brown MUDSTONE. InSection 1, 110-130 cm,WACKESTONE, red (2.5YR 5/6), withrounded small pebble-sized bivalveshells and black intraclasts. Section 2,0-68 cm contains WACKSTONE-PACKSTONE, light red (10YR 6/6)grading to white (10YR 8/2) downward,with abundant bivalve shell fragments,some molds of gastropods and rudistshells and rare black pebble intraclasts.Rare moldic porosity is developed, andshows speleothems. The originaltexture of the sediment may have beena shell debris-rich PACKSTONE but withdissolution of aragonitic debris, thesecondary cement (red) gives theappearance of a WACKESTONE.
868A-3R 1
CO
SITE 868 HOLE A CORE 4R CORED 13.1 -17.2 mbsf 868A-4R | 1
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Structureand
Components
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10YR8/2
10YR7/2
10YRR/P
Description
FLOATSTONE, WACKESTONE, andGRAINSTONE
Major Lithologies:Discrete beds of FLOATSTONE andWACKESTONE, white (10YR 8/2) tovery pale brown (10YR 8/3) and lightgray (10YR 7/2), with rudists, otherbivalves, gastropods, and red algaefragments. Section 1, 0-27 cm isstained light red (10R 6/6). Sporadicred staining occurs throughout Section1. Moldic and vuggy porosity occurthroughout. Speleothem depositsoccur in some vugs in Section 2,25-105 cm. Section 2, 82-118 cmcomprises GRAINSTONE, white (10YR8/2), poorly sorted. The grains arefragments of bivalves, and red andgreen algae, which are commonlymicritized around the edges. A 6 cmclast of massive coral occurs inSection 2, 64-68 cm.
SITE 868 HOLE A CORE 5R CORED 17.2-20.3 mbsf
Met
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Sec
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Age
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Structureand
Components
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10YR8/2
Description
FLOATSTONE
Major Lithologies:FLOATSTONE, white (10YR 8/2), withmuch rudist debris, high-spiredgastropods, sponge remains, possible
chondrodontid oysters and oncoidallycoated particles of millimeter scale.There is much solutional porosity withcommon spar-lined voids.
Minor Lithology:Local levels of GRAINSTONE occur.The Interval 55-56 cm containspossible keystone vugs in aGRAINSTONE- PACKSTONE matrix.
mC/3