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Priority:
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Alternate
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Position:
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27°44.2713′S, 117°37.1815′W (WGS 84)
(27.7379°S, 117.6197°W)
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Water depth (m)
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3688
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Target drilling depth (mbsf):
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<103 (including 100 m into basement)
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Approved maximum penetration (mbsf):
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Up to 100 m basement penetration. EPSP requested that TAMU considers the steepness of the slope.
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Previous drilling in area:
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Closest drilling:
• DSDP Leg 92 Site 599, 500 nmi away
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Comments:
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International waters; 450 nmi from Ducie Island, United Kingdom
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 3 - Shotpoint 11865 (Fig. AF19)
• Crossing line(s): MCS Line 1 - Shotpoint 11264 (Fig. AF20)
• Subbottom profile, 3.5 kHz: Line 3 - JDay 006 at 12:29 GMT
• Detailed bathymetry and site location (swath bathymetry: collected with SIMRAD EM120) (Fig. AF21)
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Sediment cores:
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One piston core, one trigger core, one gravity core, one 4 inch jumbo gravity core, and six 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.
• Determine how the basement habitats, potential activities, and communities vary with crust age and hydrologic regime (from ridge crest to abyssal plain).
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Drilling/Coring program:
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Quadruple APC to basement; RCB upper 100 m of basement
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Downhole logging program:
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None specified
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Anticipated lithology:
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Successions of brown foraminifer-bearing clayey nannofossil ooze grading to dark brown clay
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