ALTERNATE SITE SUMMARIESSite: OJ-6C (Alternate)
Position: 4°56.22´S, 164°9.30´E
Water Depth: 1705 m
Sediment Thickness: 630 m
Target Drilling Depth: 730 mbsf
Approved Maximum Penetration: 830 mbsf
Seismic Coverage: Multichannel seismic line; R/V Hakuho Maru KH98-1 Leg 2 Line 102.
Objectives: The objectives of Site OJ-6C 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 350 mbsf to the
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 350 mbsf, then RCB to bottom of hole.
Logging and Downhole: None.
Nature of Rock Anticipated: Chalk, limestone, chert, and basalt.
Site OJ-7E | Table of Contents