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Geology topics

G.D. Karner

Publications and source records attributed to G.D. Karner.

2 recordsLinked to original sources

Identifying major sedimentary basins beneath the West Antarctic ice sheet from aeromagnetic data analysis

In the Ross Sea, large sedimentary basins reflect primarily the major extensional event associated with the Late Cretaceous breakup of Gondwana. Within the Interior Ross Embayment, no similar large basins have been identified to date. We have used aerogravity and Werner deconvolution methods applied to aeromagnetic data to map depth to magnetic basement, which helped delineate three major sedimentary basins, the Bentley Subglacial, Onset, and Trunk D Basins.

Book chapter↗

Ice cover, landscape setting, and geological framework of Lake Vostok, East Antarctica

Lake Vostok, located beneath more than 4 km of ice in the middle of East Antarctica, is a unique subglacial habitat and may contain microorganisms with distinct adaptations to such an extreme environment. Melting and freezing at the base of the ice sheet, which slowly flows across the lake, controls the flux of water, biota and sediment particles through the lake. The influx of thermal energy, however, is limited to contributions from below. Thus the geological origin of Lake Vostok is a critical boundary condition for the subglacial ecosystem. We present the first comprehensive maps of ice surface, ice thickness and subglacial topography around Lake Vostok. The ice flow across the lake and the landscape setting are closely linked to the geological origin of Lake Vostok. Our data show that Lake Vostok is located along a major geological boundary. Magnetic and gravity data are distinct east and west of the lake, as is the roughness of the subglacial topography. The physiographic setting of the lake has important consequences for the ice flow and thus the melting and freezing pattern and the lake's circulation. Lake Vostok is a tectonically controlled subglacial lake. The tectonic processes provided the space for a unique habitat and recent minor tectonic activity could have the potential to introduce small, but significant amounts of thermal energy into the lake. ?? 2002 Elsevier Science B.V. All rights reserved.

Earth and Planetary Science Letters↗