At each shelf site, more than one prospective drilling location has been designated within detailed seismic "hazards" grids (Fig. 4) should unforeseen safety or operational difficulties make any particular location unsuitable. The drilling locations we will attempt to occupy first are listed in Table 1 (MAT-8B-3; MAT-9B-1). These were designated as primary locations by PPSP and the Science Operator. One additional drilling location was approved by PPSP at MAT-8B (MAT-8B 2: 39°23.0124'N, 72°43.635'W), and two were approved at MAT-9B (MAT-9B-2: 39°22.0866'N, 72°41.4024'W; MAT-9B-3: 39°21.9582'N, 72°41.5206'W).

Site: MAT-8B

There are two approved site-specific locations, designated 8B-2 and 8B-3. Both are discussed.

Position: 8B-2: 39° 23.0124'N, 72° 43.6350'W; 8B-3: 39° 22.9488'N, 72° 43.6988'W
Water Depth: 8B-2: 87 m; 8B-3: 88 m
Sediment Thickness: both sites, ~10 km
Approved Maximum Penetration: 8B-2: 1166 mbsf, 8B-3: 1165 mbsf
Seismic Coverage: 8B-2: at the crossing of seismic lines Oceanus 270 #147 (cdp 10359/shot 14.97) and #806 (cdp 10264/shot 11.00); 8B-3: at the crossing of seismic lines Oceanus 270 #806 (cdp 10288/shot 12.00) and #885 (cdp 10238/9.91) These lines are shown in accompanying figures.

Objectives: The objectives of MAT-8B are to:

1.Date major Oligocene-Holocene unconformities on the New Jersey margin and evaluate their correlation with glacial-eustatic age estimates obtained from the deep-sea d18O record; this site will concentrate on surfaces that are middle Miocene (m3) and younger.

2.Place constraints on the amplitudes and rates of sea-level change that may have been responsible for unconformity development.

3.Assess the lithostratigraphic response of changes in sequence architecture to glacial-eustatic forcing.

4.Provide a baseline for future scientific ocean drilling that will address the effects and timing of sea-level changes on this and other passive margins.

Drilling Program: Double APC/XCB to refusal holes A and B; APC/XCB to refusal, then RCB (after installation of FFF) to TD at Hole C (see Fig. 7).

Logging and Downhole Operations: Triple-Combo, FMS-Sonic, WST, VSP to TD at Hole C; Logging While Drilling* to TD at Hole D (see Fig. 7).

Nature Of Rock Anticipated: Sands, silts, and clays; subordinate gravel.

Seismic lines 8B map

Seismic section 8B-2

Seismic section 8B-3

Seismic section 8B-3 and 8B-2

*LWD tools: CDR, CDN (see preceding text).

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