Sites GAB-01C, GAB-02B, and GAB-13B
Sites GAB-01C (southern Australian upper continental rise), GAB-02B (mid-upper slope), and alternate GAB-13B (middle continental rise) are paleoceanographic sites located to intersect pelagic sections that collectively span the entire Cenozoic succession and a substantial part of the Late Cretaceous section. These sites compose the deeper water component of the shelf-to-basin transect. The principal objective at these sites is to obtain a complete record of the Cenozoic section in a deep oceanic setting, with the principal aim of elucidating the evolution of the Circum-Antarctic Current within the evolving seaway between Australia and Antarctica. As the condensed section in the Jerboa-1 well contains early Oligocene faunas, there is a high probability that the intermediate and deep pelagic successions will together contain a more expanded record of this critically important time of Antarctic ice-cap evolution and Southern Ocean paleoceanographic development.
Sites GAB-03B and GAB-04B
Sites GAB-03B and GAB-04B are located to intersect the Eocene to early middle Miocene section deposited in lobes on the upper slope, coeval with deposition of the extensive carbonate platform on the continental shelf. In addition, these sites will also intersect an early Neogene succession poorly sampled at other sites; a highly condensed late Neogene succession; and the upper part of the marine Cenomanian section at Site GAB-04B. The principal objective at these sites is to collect a detailed record of Paleogene-early Neogene temperate to subtropical, mid-latitude sedimentation in an upper slope environment and to recover a record of marine flooding of the evolving rift basin in the Cenomanian (Site GAB-04B).
Sites GAB-05B and GAB-06B
Sites GAB-05B and GAB-06B are located to intersect distal (Site GAB-05B) and proximal (Site GAB-06B) parts of the Paleocene to middle Eocene progradational siliciclastic wedge. In addition, these sites will intersect a major portion of the overlying Neogene succession (Seismic Sequences 2 to 4). The principal objective at these sites is to recover a detailed record of shelf-edge siliciclastic deposition to evaluate the sedimentary response to Paleogene sea-level fluctuations and to evaluate the complex interaction between sea-level variation, accommodation space, and subsidence evident in stratal patterns.
Sites GAB-07A, GAB-08A, and GAB-09A
Sites GAB-07A, GAB-08A (alternate), and GAB-09A will intersect a spectacular set of late Neogene (?Plio-Pleistocene) clinoforms immediately seaward of the present-day shelf edge. Site GAB-07A will intersect the lowest, more condensed portion of the clinoform sequence, but will also have the best record of the youngest clinoforms; Site GAB-08A will intersect a ?Pleistocene Holocene biogenic mound immediately below the seafloor, together with the best record of the middle part of the clinoform sequence; and Site GAB-09A will intersect a buried biogenic mound originally formed immediately below the paleoshelf edge, together with the best record of the oldest part of the clinoform sequence. The principal objective at these sites is to collect detailed, high-resolution profiles through a late Neogene shelf-edge (high energy) to upper slope (low energy) succession deposited within a cool-water carbonate environment to determine the response of such a depositional system to Plio-Pleistocene sea-level fluctuations.
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