University of Texas at Arlington, United States

Site 1073A was drilled on the upper continental slope (water depth 665 m) off New Jersey as part of the ODP Leg 174A New Jersey Sea-Level Transect and was designed to study glacio-eustatic changes on a passive margin. Sedimentological and geochemical data are used to reconstruct a high-resolution sea-level record from the thick (520 m) Pleistocene section recovered at this site. Sedimentation rates of approximately 900 m/my permit the resolution of small-scale variability that is related to sea-level change. Seismic data show that the Pleistocene sediment at Site 1073A is relatively undisturbed and an extensive array of seismic lines provide the necessary control to correlate from the shelf drill sites (Leg 174A Sites 1071-1072) to the slope drill sites (Site 1073 and Leg 150 Sites 902-904). Oxygen-isotope chemical stratigraphy derived from the tests of Globorotalia inflata and stratigraphy derived from CaCO (sub 3) analyses reveal a correlation between high CaCO (sub 3) (up to 30%) and low oxygen isotope signatures (delta (super 18) O PDB 1.5-2.5) and vice-versa. This variability suggests glacial-interglacial cycles. A higher-order variability is indicated by an inverse correlation between the relative abundance of quartz and iron-rich minerals and calcite. Other proxies: spectrophotometry data and opal and organic carbon analyses will be used to further constrain these findings. The timing of these events will be determined from Accelerator Mass Spectrometry (super 14) C dates.