170 Prospectus

Site CR-3

Priority: 1
Position: 9°43.8'N, 86°7.2'W
Water depth: 3320 m
Sediment thickness: 1400 m
Total penetration: 1400 mbsf (approved to a depth of 1400 mbsf)
Seismic coverage: 3D seismic reflection data (3D Line 177; 3D cross Line 450)

Objectives: The objectives of CR-3 are to:

1. Determine the age and physical properties of the sedimentary apron.

2. Penetrate beneath the high amplitude reflector and determine the nature of the material beneath this layer.

3. Penetrate to the zone of out-of-sequence thrusting and determine the nature of material above and below this layer.

4. Use the results of the drilling to compute a mass balance between incoming and accreted strata.

Drilling program:
Hole A: APC/XCB with Adara tool to 500 mbsf plus 5 WSTP measurements
Hole B: Reentry cone, set 10-3/4" casing to 500 mbsf, RCB to 1400 mbsf
Hole C: Drill with LWD tools to 1400 mbsf

Logging and downhole: Logging while drilling

Nature of rock anticipated: Hemipelagic mudstone and carbonate-rich pelagic mudstone. Possibly serpentine and/or mafic rocks at depth.

To Seismic Profile CR-3

To Site CR-4

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