Priority:
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Alternate
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Position:
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28°26.03′N, 142°46.02′E
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Water depth (m):
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4762
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Target drilling depth (mbsf):
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960 (210 m sediment, 750 m basement)
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Approved maximum penetration (mbsf):
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1460 (pending EPSP approval)
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Survey coverage:
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Line IBr11 CDP 68768
• Track map (Fig. AF1)
• Seismic profiles (Figs. AF2, AF4, AF6) |
Objective:
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Characterize lower volcanic stratigraphy at Bonin fore arc to investigate subduction initiation processes and test supra-subduction zone ophiolite models
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Drilling, coring, and downhole measurements program:
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• Hole A: jet-in test
• Hole B: APC/XCB to basement (210 mbsf)
• Hole C: reentry system (16 and 10-3/4 inch casing to 215 mbsf)
• Hole C: drill without recovery to 220 mbsf, RCB from 220 to 960 mbsf
• FlexIT core orientation measurements
• Wireline logging (triple combo, FMS-sonic)
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Nature of rock anticipated:
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Pelagic carbonate with thin ash layers, basaltic lavas, and sheeted dikes
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