Priority: 1
Position: 67°34.00'S, 76°57.78'W
Water Depth: 3200 m
Sediment Thickness: >2000 m
Approved Maximum Penetration: 1450 mbsf
Seismic Coverage: Explora Lines IT92-109 and AI95-130
Objectives: The objectives of Site APRIS-01A are to:
1. Obtain a high-resolution history of Antarctic Peninsula glaciation for the last 6-10 m.y. from the long continuous sediment succession of the hemipelagic sediment drifts.
2. Determine the onset of drift formation by sampling the base of Unit M4.
Drilling Program: Double APC to 200 m and XCB (or RCB if necessary) to 700 m, then either
RCB from 700 m to base of M4 at same site OR single APC and XCB to base M4 (at ~550 m) at
offset site (APRIS-02A), where upper section is thinner. Offset is required if stratigraphic control
seriously degrades below the silica diagenetic BSR at about 600 m. Alternate sites: APRIS-03A
and 05A.
Logging and Downhole Operations: Standard suites IPLT-DLT and FMS-sonic, plus GHMT.
Vertical incidence VSP.
Nature of Rock Anticipated: Alternating (interglacial) biosiliceous clay and (glacial) laminated
barren gray clay, becoming claystone downhole.