The Petroleum System as an Exploration Tool in a Frontier Setting

SMITH, JOHN T., Shell Oil Company Consultant

Use of the petroleum system concept as an exploration tool requires synthesis of the influence of three geological processes connected in space and time to create each petroleum system. These three processes are the generation, migration, and trapping of petroleum. An evaluation procedure that makes this synthesis provides a logical mechanism for ranking the conceptual petroleum systems in a given frontier area with respect to hydrocarbon charge questions.

In a frontier area this evaluation procedure starts with a regional geologic model of the area based on a seismic grid calibrated to the available stratigraphic control. This model should go to basement, that is, to a layer deep enough to include all potential source rocks for those conceptual petroleum systems of interest. This model should be developed using seismic stratigraphy methods to define depositional sequences, major transgressions, and regressions related to global sea-level changes, paleo-topography and other characteristics important for predicting and extrapolating source rocks, reservoirs, and seals. If the area has a complex tectonic history, several models may be required, each representing a different stage in the evolution of the area. Considerable experience has b en gained over the past 23 years in the application of this approach to evaluate hydrocarbon charge questions in the frontier area of North America. Examples drawn from this experience will be presented to illustrate successes, failures, and difficulties of prediction based on the petroleum system concept.

AAPG Search and Discovery Article #91004 © 1991 AAPG Annual Convention Dallas, Texas, April 7-10, 1991 (2009)