IODP

doi:10.2204/iodp.sp.344.2012

Site summaries (continued)

Site U1378 (Proposed Site CRIS-3B)

Priority: Alternate
Position: 8°35.54136′N, 84°4.63062′W
Water depth (m): 522
Target drilling depth (mbsf): 1000 (890 m sediment, 110 m basement)
Approved maximum penetration (mbsf): 1000
Survey coverage: Line BGR 99-7 CMP 2500
• Track map (Fig. AF1)
• Seismic profile (Fig. AF4)
• Location map (Fig. F6)
Objective: Alternate for U1380. Characterize upper plate basement and fluid flow.
Drilling, coring, and downhole measurements program: • Hole C: jet-in test for reentry system.
• Hole D: reentry system (20 and 16 inch casing to 260 mbsf).
• Hole D: drill without recovery to 450 mbsf, RCB from 450 to 1000 mbsf.
• Wireline logging (triple combo-UBI, FMS-sonic, VSI).
Nature of rock anticipated: Sediments: mud and silt, mud-supported breccia. Basement: shaly matrix breccia with carbonate, cherty, and basaltic clasts.