Seismic-reflection signature of cretaceous continental breakup on the Wilkes Land margin, Antarctica

Stephen Eittreim; Monty A. Hampton; Jonathan R. Childs

doi:10.1126/science.229.4718.1082

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Seismic-reflection signature of cretaceous continental breakup on the Wilkes Land margin, Antarctica

Stephen Eittreim·Monty A. Hampton·Jonathan R. Childs

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Abstract

The passive (rifted) continental margin of Wilkes Land, Antarctica, is characterized on seismic reflection records by (i) in the south, a block-faulted sequence of highly stratified continental beds overlain by two distinct unconformities; (ii) a transitional, greatly thinned continental crust overlain by material interpreted to be flood basalt; and (iii) in the north, oceanic crust with a boundary ridge at its edge. The Mohorovičić discontinuity can be followed across the continent-ocean boundary and shows a progressive thinning of continental crust to a minimum of 2.5 kilometers at its northern edge.

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Source-reported bounding extent: -73.81291685672498° to -66.43733266250635° latitude; 118.42749253388467° to 159.71840003397233° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Stephen Eittreim, Monty A. Hampton, Jonathan R. Childs. 1985. Seismic-reflection signature of cretaceous continental breakup on the Wilkes Land margin, Antarctica. https://doi.org/10.1126/science.229.4718.1082

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