Priority:
|
Alternate
|
Position:
|
28°25.63′N, 142°43.50′E
|
Water depth (m):
|
4452
|
Target drilling depth (mbsf):
|
1020 (270 m sediment, 750 m basement)
|
Approved maximum penetration (mbsf):
|
1520 (pending EPSP approval)
|
Survey coverage:
|
Line IBr11 CDP 68100
• Track map (Fig. AF1)
• Seismic profiles (Figs. AF4, AF9) |
Objective:
|
Characterize lower volcanic stratigraphy at Bonin fore arc to investigate subduction initiation processes and test supra-subduction zone ophiolite models
|
Drilling, coring, and downhole measurements program:
|
• Hole A: jet-in test
• Hole B: APC/XCB to basement (270 mbsf)
• Hole C: reentry system (16 and 10-3/4 inch casing to 275 mbsf)
• Hole C: drill without recovery to 280 mbsf, RCB from 280 to 1020 mbsf
• FlexIT core orientation measurements
• Wireline logging (triple combo, FMS-sonic)
|
Nature of rock anticipated:
|
Pelagic carbonate with thin ash layers, basaltic lavas, and sheeted dikes
|