Site 1140 lies on the northernmost part of the Kerguelen Plateau, ~270 km north of the Kerguelen Archipelago (Fig. F1). Flanked to the north and east by Eocene and younger oceanic crust of the Australian-Antarctic Basin, and to the west by Cretaceous oceanic crust of the Crozet and Enderby basins, the northern Kerguelen Plateau (NKP) is believed to have formed since 40 Ma via Kerguelen hot spot magmatism (Royer and Sandwell, 1989; Royer and Coffin, 1992). The Kerguelen Archipelago is part of the NKP; its igneous rocks yield dates from 39 Ma to the Holocene (Nicolaysen et al., 1996, in press). However, submarine igneous basement of the NKP has never been sampled, so its age and composition, as well as its relationship to the central and southern plateau sectors and to Skiff and Elan Banks, are unknown. We located Site 1140 on Marion Dufresne multichannel seismic (MCS) line MD109-06 (Fig. F2). Site 1140 lies at a depth of 2394 m on the northern flank of the NKP. We chose this location as representative of the NKP on the basis of its relatively simple structural setting and thin sedimentary section (Fig. F3). The top of acoustic basement is flat lying, and overlying basement is a sediment sequence ~350 m thick. The boundary between the NKP and the Australia-Antarctic Basin lies ~5 km north of Site 1140 and offsets basement by ~400 m.
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