View larger version (75K):
[in this window]
[in a new window]
|
Figure 1. Topography and inferred structure (inset) of the Marie Byrd Land sector of the West Antarctic rift system showing simplifi ed ice-free, iso-statically adjusted bedrock topography (Drewry, 1983), Marie Byrd Land dome, and Ross Sea basins (Cooper et al., 1991; Cande et al., 2000). The Marie Byrd Land dome is defi ned by contours on the late Cretaceous West Antarctic erosion surface (LeMasurier and Landis, 1996). All four deep interior basins described in the text extend below –1500 m (blue). The "rift trough," referred to in the text, is the sub-sealevel region between the Marie Byrd Land dome and Transantarctic Mountains that extends from the Ross Sea to the Bellingshausen Sea. Note that topographic slopes along most of the Transantarctic Mountain front are too steep to represent each contour interval at this scale. Abbreviations: BST—Bentley Subglacial Trench; C—CASERTZ aerogeophysical volcano (Blankenship et al., 1993); CT—Central Trough; EB—Eastern Basin; EM—Ellsworth Mountains; MBL—Marie Byrd Land; Pt—Mount Petras; RI—Ross Island; Tn—Toney Mountain; VL—Victoria Land; VLB—Victoria Land Basin; WAES—West Antarctic erosion surface; WM—Whitmore Mountains.
|
