Site 1130 is located on the Great Australian Bight upper slope in 488.0 m of water (Fig. F1). The primary objective at Site 1130 was to intersect and characterize Neogene shelf edge and slope sequences and, particularly, to sample the distal (to contrast with the proximal section at Site 1132) portion of an inferred Paleocene-middle Eocene progradational siliciclastic wedge identified and mapped as seismic Sequence 7 (Feary and James, 1998, reprinted as Chap. 2). This sequence forms an east-west-oriented, elongate sediment body that extends at least 300 km along the Eucla Basin, seaward of a prominent basement high (Fig. F2; see "Seismic Stratigraphy").
Sequence 7 appears to represent the first depositional episode overlying the top Mesozoic erosional event. The uppermost portion of this sequence is probably the seaward equivalent of the middle Eocene Hampton Sandstone found in the subsurface of the onshore Euclato be Basin. The youngest parts of Sequence 7 were inferred thin, uppermost lower or lowermost middle Eocene mudstones intersected at the base of the Tertiary succession in the Jerboa-1 well (Bein and Taylor, 1981; Stagg et al., 1990), and interpreted by Feary and James (1998, reprinted as Chap. 2) as a thin foredelta apron. This top part of the sequence is an aggradational component reflecting increased accommo-dation space, probably resulting from sediment compaction and sag within the Mesozoic rift basin (Eyre Sub-basin) underlying the Eyre Terrace.
Site 1130 was located to intersect thin portions of Paleogene Sequence 6A and Neogene Sequence 4, overlain by a thick interval of Pleistocene Sequence 2. Regional seismic stratigraphy shows that Sequences 6A and 4 are deep-water carbonate accumulations with lobate and aggradational geometries, respectively (see "Seismic Stratigraphy"). Sequence 2 at Site 1130 offered the opportunity to describe along-slope variations in sedimentation rates and facies, in comparison with the much thicker interval of Sequence 2 intersected at Sites 1127, 1129, and 1131.
The scientific objectives for Site 1130 were to
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