Abstract: Development Regimes of Rifted Basins and Criteria of Their Petroleum Potential

Evgeny Larchenkov

The majority of great sedimentary basins were formed primarily by stretching and usually initiated by rifting. The evolution and development of intercontinental and passive margin rifted basins are discussed. Each basin type described (in the paper) are associated with either single or branched rift zones. The basin types are (1) unburied rift, i.e., recent rifts, or ancient rifts with post-rift stage without significant subsidence such as East Africa rifts, and Reconcavo basin in Brazil; and (2) buried rift zones where the post-rift stage is characterized by active subsidence and sediment accumulation.

The basins often form by repeated rifting, and a rift zone of a different age may be completely or partially superimposed or separated from other rifting events.

By analysis of the history of tectonic evolution and the history of hydrocarbon generation in many rifted intracontinental basins of Eurasia and passive continental margins of the Atlantic and Indian oceans, rift basins have been recognized with early and late hydrocarbon generation and migration.

Criteria have been established in the recognition of the development of rifted basins and their petroleum potential. Important criteria in establishing the petroleum potential of rifted basins are repeated rifting, repeated tectonic activity in the Cenozoic, and superposition of rift zones of different ages. Intracratonic rifted basins associated with sheer zones are generally more prospective than those formed by strike-slip motion.

Analysis of the development regime of rifted basins is a very important part in determining the approach for petroleum prospecting in sedimentary basins.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994