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Main facies
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Subfacies
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Facies
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Description
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Marine microfossils
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Lithostratigraphic
unit
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Tentative depositional
environment/diagenesis
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Mud
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Massive mud with lonestones
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F1a
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Dark gray to (dark) greenish gray;
Bioturbated (none to heavy);
Occasionally calcareous bearing;
Occasionally diatom rich/bearing;
Lonestones of granule and pebble sizes occur in varying amounts;
Occasional color banding and black mottles;
Occasional sand pods;
Interbedded with Facies F1b, F2a, F2b, F3a, F3b, F3c, F4a, F4b, F4c, F4d, F5a, F5b, F5c, F6, F7, and F8.
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Variable
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IA, IB, II, III, IV, VA, VB, VC, VD, VE, VG, VI
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Suspension fall-out, ice rafting, or sediment gravity flows
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Massive mud without lonestones
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F1b
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Dark gray to (dark) greenish gray;
Bioturbated (none to heavy);
Occasional Zoophycos burrows;
Occasionally calcareous bearing;
Occasionally diatom rich/bearing;
Occasional color banding and black mottles;
Occasional silt pods/lenses;
Interbedded with Facies F1a, F2a, F2b, F3a, F3c, F4a, F4c, F4d, F5a, F5b, F5c, F6, and F7.
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Diatoms may occur
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IA, IB, II, IV, VA, VB, VC, VD, VE, VG, VI
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Suspension fall-out, ice rafting, or sediment gravity flows
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Silt
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Silt
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F2a
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Dark gray to greenish gray;
Often interbedded with mud;
Sharp to gradational upper and lower contacts;
Diatoms may occur;
Interbedded with Facies F1a, F1b, F2b, F3a, F4d, F5a, F5b, F5c, F6, and F7.
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Diatoms may occur
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IA, IB, II, VE, VF, VG, VH, VI
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Sediment gravity flows
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Interbedded silt and mud
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F2b
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Dark gray to greenish gray;
Facies thickness 2 to 360 cm;
Occasional color banding;
None to moderate bioturbation;
Occasionally with terrestrial organic components;
Interbedded with Facies F1a, F1b, F2a, F3a, F4d, F4e, F4f, F6, and F8.
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Not documented
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IA, II, VE
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Mud: suspension fall-out from surface water plumes and from sediment gravity flows
Silt: sediment gravity flows
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Sand
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Very fine to coarse sand
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F3a
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Dark gray to gray;
Bed thickness from 1 to 5 cm, occasionally thicker;
Massive and normal grading;
Sharp and frequently erosional lower contacts;
Gradational and sharp upper contacts;
Composition includes quartz and feldspar;
Interbedded with Facies F1a, F1b, F2a, F2b, F4b, F4d, F5a, F5b, F5c, and F6.
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Not documented
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IA, IB, II, IV, VA, VB, VC, VE, VG, VI
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Sediment gravity flows
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Medium to coarse sand
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F3b
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Dark gray to gray;
Bed thickness up to 40 cm;
Rip-up clasts common;
Plant debris, organic matter, and diatoms may occur;
Sharp bases and sharp to gradational upper contacts;
Interbedded with Facies F1a and F4b.
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Not documented
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VA
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Sediment gravity flows
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Interbedded sand and mud
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F3c
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Dark gray to dark greenish gray;
Facies thickness 7–710 cm;
Partly diatom bearing;
None to moderate bioturbation;
Partly with volcanic ash;
Occasional color banding;
Lonestones may occur;
Interbedded with Facies F1a, F1b, F5a, F5b, F5b, F6, and F7.
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Diatoms may occur
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IB, II, VA
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Suspension fall-out from surface water plumes (mud), ice rafting (mud, sand, lonestones), and sediment gravity flows (sand, mud)
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Diamict
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Muddy diamict
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F4a
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Dark gray;
Muddy matrix;
Clast concentration variable;
Thin bedded or pods;
Lower contacts are gradational;
Upper contacts are sharp and defined by concentration of clasts;
Granule and small pebble clasts are commonly subangular to subrounded;
Interbedded with Facies F1a and F5c
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Not documented
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IB, III
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Suspension settling and ice rafting (mainly by icebergs)
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Muddy and sandy diamict with lithic and mud clasts and/or terrigenous organic components
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F4b
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Dark gray;
Mud to sand matrix;
Bed thickness up to 40 cm;
Sharp upper and lower contacts;
Lithic and mud clasts up to 3 cm;
Occasional plant debris and terrestrial organic components (coal?);
Interbedded with Facies F1a, F1b, F3a, F3b, F5a, F5b, F7, and F8 (in disturbed sequence).
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Diatoms (partly freshwater)
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VA, VC, VD, VE, VF, VG, VI
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Sediment gravity flows
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Breccia
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F4c
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Dark gray matrix;
Sandy mud matrix;
Bed thickness typically 100 cm;
Sharp erosive lower contacts;
Gradational upper contacts;
Most often clasts of indurated diatom ooze;
Interbedded with Facies F1a and 5a.
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Not documented
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VF
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Sediment gravity flows (e.g., slump)
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Interbedded mud and diamict
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F4d
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Dark gray to greenish gray;
Occasional color banding and parallel lamination;
None to moderate bioturbation;
Occasionally calcareous bearing;
Interbedded with Facies F1a, F1b, F2a, F2b, F3a, F4e, F5b, F5c, and F7.
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Not documented
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III, VC, VE
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Suspension settling and ice rafting (icebergs and/or sea ice)
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Diatom ooze
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F5a
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Greenish gray;
20 cm to 1.5 m;
Bioturbation (including Zoophycos burrows);
Sharp to gradational upper and lower contacts;
Interbedded with Facies F1a, F1b, F2a, F3a, F3c, F4b, F4c, F5b, and F6.
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Diatoms and other biosiliceous material; occasional carbonate (foraminifers and coccolithophores)
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IA, IB, II, VA, VB, VD, VF, VH, VJ
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High-productivity environment and/or low terrigenous input and/or better preservation
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Biosiliceous ooze; biosiliceous-rich/bearing mud and sand; mud with diatoms/biosilica
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F5b
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(Very) dark gray to (dark) greenish gray and brown;
Facies thickness 2–445 cm;
Mostly mud, rarely sand;
Diatom and biosiliceous rich/bearing;
Lonestones are absent or present;
Occasional color banding;
Partly mottled;
Occasionally laminated;
None to heavy bioturbation;
Interbedded with Facies F1a, F1b, F2a, F3a, F3c, F4b, F5a, F5c, F6, F7, and F8.
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Diatoms and other biosiliceous material
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IA, IB, II, IV, VA, VB, VC, VD, VE, VH, VI
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High-productivity environment and/or low terrigenous input and/or better preservation
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Calcareous/carbonate-bearing/rich mud, silt, sand, diamict, and/or diatom ooze
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F5c
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(Very) dark gray to greenish gray;
Facies thickness 3–316 cm;
Occasionally with volcanic ash;
None to heavy bioturbation;
Occasional color banding and lamination;
Interbedded with Facies F1a, F1b, F2a, F3a, F4a, F4b, F5b, and F8.
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Foraminifers; occasionally diatoms
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II, III, IV, VB, VE, VI
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Temporarily increased productivity and/or reduced suspension settling and/or better preservation
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Ash
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Volcanic ash
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F6
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Usually gray to brown;
Bed thickness typically 1–5 cm;
Sharp lower contacts;
Sharp to gradational upper contacts;
Primarily vitric shards (glass);
Some intervals affected by bioturbation;
Often interbedded with Facies F1a, F1b, F2a, F3a, F3c, F5a, and F5b.
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Not documented
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IA, IB, II, VA
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Suspension settling after subaerial eruptions
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Volcaniclastic mud, sand, diamict and/or ooze
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F7
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Usually grayish, greenish, or brownish;
Bed thickness typically 1–5 cm;
Sharp and frequently erosive lower contacts;
Gradational to sharp upper contacts;
Primarily vitric shards (glass);
Some intervals affected by bioturbation;
Often interbedded with Facies F1a, F1b, F2a, F3c, F4d, F5b, and F7.
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Diatoms
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IA, IB, II, III, IV
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Volcanic detritus either bioturbated or reworked/redeposited by sediment gravity flows
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Rock
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F8
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Siltstone with carbonate cement;
Often interbedded with Facies F1a, F2b, F4b, F5b, and F5c.
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VC, VE, VH
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In situ carbonate sedimentation
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