SITE SUMMARIES (continued)
Site: PCM-4A
Priority: 4 (or 3 if PCM-2A yields volcanic architecture)
Position: 3°44.445'S, 151°40.755'E
Water Depth: 2139 m
Sediment Thickness: 10-20 cm ooze
Target Drilling Depth: 350 m
Approved Maximum Penetration: 350 mbsf
Seismic Coverage: Sonne SO-94/SCS-07 Leg 2; 150 m abeam CDP1785
Objectives: The objectives of PCM-4A are to determine the
1. Heat flow and alteration at a potential seawater influx zone;
2.Intersect and characterize a presumed low angle extensional fault controlling Pual Ridge eruption (at ca 250 m); and
3. Test arc crust basement beneath 150 m basaltic andesite flow sequence.
Drilling Program: TBD after evaluating the results of drilling at Site PCM-2A. Options include
bare-hole reentry, free-fall funnel deployment and/or a reentry cone. Requires multiple reentry to
achieve depth target.
Logging and Downhole: Fluid and temperature sampling as required. Triple combo, FMS/sonic,
logging while drilling.
Nature Of Rock Anticipated: Basaltic andesite lavas, metavolcanics (basement), fault gouge.