Hydrocarbon traps occur in a variety of plate tectonic settings, each imparting a certain control on the depositional and diagenetic aspects of carbonate reservoirs. A knowledge of trap-type in each tectonic environment is very useful for defining exploration concepts in frontier regions where paucity of subsurface information forces the explorationist to depend solely on seismic data.

In the extensional plate-tectonic setting, during the early stage of rifting, carbonate traps can form on shoals marginal to fresh-water lakes which occupy intra-cratonic grabens. The post-breakup transgression generally results in deposition of salt which is overlain by a carbonate shelf. Salt tectonics control the configuration of carbonate traps as well as the depositional and diagenetic aspects of the reservoir. Within rifted continental margins, a majority of the carbonate traps occur in shelf facies behind ocean-facing reef complexes which are generally cemented in the marine environment. Shelf-margin reefal complexes which were subsequently subjected to a late tectonic phase may be viable exploration targets.

In a convergent plate-tectonic setting, carbonate shelves marginal to the backarc basin are ideal sites for hydrocarbon accumulations. Within the continental-collision setting, carbonate ramps on the cratonic side of foreland basins provide for major hydrocarbon accumulations. Carbonate formations involved in overthrust structures can be sites of giant petroleum accumulations.

The trans-tensional and the trans-compressional wrench-fault setting can create favorable environmental and diagenetic conditions for carbonate traps.

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