SITE SUMMARIES (continued)Site: PCM-2A
Position: 3°43.690'S, 151°40.200'E
Water Depth: 1655 m
Sediment Thickness: 0 m
Target Drilling Depth: up to 700 m
Approved Maximum Penetration: 500 mbsf
Seismic Coverage: Sonne SO-94/SCS Leg 2, CDP 1720
Objectives: The objectives of PCM-2A are to determine the
1.Subsurface alteration and mineralization patterns, and their variation with depth, beneath an area of diffuse, low-temperature venting and acid sulfate alteration;
2. Hydrothermal fluid pathways;
3. Possible existence of subhalative massive sulfide bodies; and
4. Volcanic architecture if detectible through alteration.
Drilling Program: Bare rock spud with 9-7/8-in RCB. Drill until ±50 rotating hours or depth in excess of 250 mbsf. Bare-hole reentry with ADCB and core to target depth (TD). Alternate strategy if BHR fails is to drill large diameter pilot hole, insert free-fall funnel, core to TD. If hole stability is problematic, we may decide to deploy a reentry cone with casing.
Logging and Downhole: Fluid and temperature sampling as required. Triple combo, FMS/sonic, logging while drilling.
Nature Of Rock Anticipated: Altered and fresh dacite lava and hyaloclastite, mineralized veins.
Site: PCM-3A | Table of Contents