ABSTRACT: Petroleum Geology of Western Antarctica
Antarctica's geology is mostly obscured by thick, moving ice that covers 95% of the land and continental shelf. Reconnaissance investigations of outcrops, shallow boreholes, and geophysical surveys are limited and peripheral owing to ice coverage. However, it is possible to outline substantial elements of the regional geology. Further insight is gained by comparison to analogous sedimentary provinces, especially provinces once adjoined within the framework of the Gondwana supercontinent until middle Cretaceous.
The petroleum potential of Antarctica, as in the case of the other related high-standing Gondwana continental fragments, is in Early Cretaceous rifts associated with the Gondwana breakup and with the Pacific convergence in the west Antarctica back arc. The Pacific-facing western Antarctica includes two structural provinces: (1) the Cretaceous and younger interior rift system on the east side of the Weddell and Ross Sea embayments, which contain aulacogens that form the boundary with East Antarctica, and (2) the back-arc and fore-arc basins adjoining the Antarctica Peninsula and extending into Marie Byrd Land and the Bellingshausen Sea, which are associated with the eastward convergence of the Pacific plate. The petroleum potential of the rifts may be assessed by analogies with related rifts of Australia, India, and South Africa; assessment of the convergent basins of western Antarctica depends upon analogy with similar basins of South America, New Zealand, and Indonesia.
An estimate of the petroleum potential of western Antarctica generally is comparable with oil and gas occurrences (both in overall quantity and in field sizes) in the other Gondwana continental fragments. However, in view of the thick moving ice cover, the remote locale, and severe climate, petroleum production is largely beyond technology at this time and probably is economically unfeasible.
AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990