DAVIS, JOSEPH R., Davis Exploration Consulting, Dallas, TX

ABSTRACT: Exploration for Stratigraphic Traps in Frontier Basins

Stratigraphic plays require an analysis of seal, source, maturation, and timing as well as the more commonly-studied play elements of trap and reservoir. Thus, many explorationists tend to think of stratigraphic plays as better-suited for mature basins, where comprehensive datasets can by utilized. However, there are numerous examples of the discovery of large stratigraphic and combination accumulations during the frontier eras of many basins (for example: Prudhoe Bay, East Texas, Kern River, Cerro Azul, Amal, and Sarir). Thus, it is important to evaluate the potential for stratigraphic trapping with the sparse data commonly encountered in frontier basins. Genetic basin classification is well-adapted for this purpose, because the association of specific stratigraphic plays with partic lar basin types allows the explorationist to focus upon a few play possibilities in a given basin.

Vertically-drained, high impedance basins are well-suited to many types of stratigraphic accumulations. These basins are particularly associated with giant accumulations in carbonate reefs (Permian Basin, Tampico Basin, Sirte Basin) and depositional traps, such as submarine fans (Permian Basin, North Sea, Campos Basin), but large accumulations associated with both carbonate and clastic facies-changes are also possible (U.S. Gulf Coast, Maracaibo Basin). Large stratigraphic accumulations trapped beneath regional unconformities are typically associated with laterally-drained, high impedance basins (Prudhoe Bay, East Texas, Shuaiba). Laterally-drained, low impedance basins such as the Williston and Denver Basins typically are associated with sub-giant stratigraphic accumulations of hydro arbons trapped by both carbonate and clastic facies-changes.

AAPG Search and Discovery Article #90987©1993 AAPG Annual Convention, New Orleans, Louisiana, April 25-28, 1993.