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Priority:
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Primary
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Position:
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39°18.6158′S, 139°48.0381′W (WGS 84)
(39.3103°S, 139.8006°W)
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Water depth (m)
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5283
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Target drilling depth (mbsf):
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21
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Approved maximum penetration (mbsf):
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Until basement is encountered
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Previous drilling in area:
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Closest drilling:
• DSDP Leg 92 Site 597, 1350 nmi away
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Comments:
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International waters; 750 nmi from Rapa, French Polynesia
Preferred weather window: November–December
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Survey coverage
(track map, seismic profile):
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High-resolution seismics:
• Primary Line(s): MCS Line 6 - Shotpoint 15516 (Fig. AF25)
• Crossing line(s): MCS Line 4 - Shotpoint 14861 (Fig. AF26)
• Subbottom profile, 3.5 kHz: Line 6 - JDay 013 at 16:03 GMT
• Detailed bathymetry and site location (swath bathymetry: collected with SIMRAD EM120) (Fig. AF27)
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Sediment cores:
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Two piston cores, three trigger cores, one gravity core, and seven cores of an eight-barrel multicore
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Objectives
(see text for complete details):
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• Document the habitats, metabolic activities, genetic composition, and biomass of microbial communities in subseafloor sediments with very low total activity.
• Test how oceanographic factors (such as surface ocean productivity) control variation in sedimentary habitats, activities, and communities from gyre center to gyre margin.
• Quantify the extent to which these sedimentary communities may be supplied with electron donors by water radiolysis, a process independent of the surface photosynthetic world.
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Drilling/Coring program:
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• Triple to quadruple APC to basement
• Temperature measurements: APCT-3
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Downhole logging program:
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None specified
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Anticipated lithology:
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Homogeneous brown clay with yellowish brown circular mottles; baseball-sized manganese nodules present at top
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