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SITE SUMMARIES (continued)

Site: PCM-8A

Priority: Alternate for, or supplement to, PCM-3A
Position: 3°43.790'S, 151°40.015'E
Water Depth: 1690 m
Sediment Thickness: 0 m
Target Drilling Depth: 300 m (continue if conditions allow and results justify)
Approved Maximum Penetration: Not reviewed by SSP, center of Tsukushi chimney field
Seismic Coverage: Sonne SO-94/SCS Leg 2, abeam CDP 1710



Objectives: The objectives of PCM-8A are to determine the

1.Subsurface alteration and mineralization patterns, and their variation with depth, beneath an area of focused, high-temperature venting;

2. Hydrothermal fluid pathways; and

3. Thickness of exhalative sulfides, and nature of mound beneath chimneys.



Drilling Program: Bare rock spud, reentry may be required to meet depth objectives. Alternate drilling strategy may be employed based on the results of operations at Site PCM-2A. Options include bare-hole reentry, free-fall funnel deployment, and/or a reentry cone.


Logging and Downhole: Fluid and temperature sampling as required. Triple combo, FMS/sonic, logging while drilling.


Nature Of Rock Anticipated: Fresh and altered dacite lava, mineralized veins, possible massive sulfide intervals

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