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Site: OJ-11C
Seismic Line

Priority: 2
Position: 0°21.46´S, 161°40.06´E
Water Depth: 3915 m
Sediment Thickness: 330 m
Target Drilling Depth: 430 mbsf
Approved Maximum Penetration: 530 mbsf
Seismic Coverage: Multichannel seismic line; R/V Hakuho Maru KH98-1 Leg 2 Line 401.

Objectives: The objectives of Site OJ-11C are to

1. Obtain a minimum of 100 m of basaltic basement to determine lava composition and age.

2. Determine lava-flow thickness and flow morphology and, hence, deduce eruptive environment.

3. Obtain sedimentary record and determine sequence facies from 250 mbsf to the
sediment/basement interface.

4. Determine a minimum basement age using overlying sediments and ages of possible sediment

5. Define the ages of seismic sequence boundaries.

6. Determine early subsidence history and duration of possible subaerial environment.

Drilling Program: Drill without coring to 250 mbsf, then RCB to bottom of hole.

Logging and Downhole: None.

Nature of Rock Anticipated: Chalk, limestone, chert, and basalt.

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