ABSTRACT: Interior Cratonic Basins
LEIGHTON, MORRIS W., DENNIS R. KOLATA, DONALD F. OLTZ, and J. JAMES EIDEL, Illinois State Geological Survey, Champaign, IL
Interior cratonic basins are thick accumulations of predominantly sedimentary rocks that occur in subcircular to ovate depressions on continental crust. Further, they are typified by dominance of flexural over fault-controlled subsidence, low ratio of sedimentary rock volume to surface area of the basin, and episodic subsidence that
occurred over spans of hundreds of millions of years. A review of interior cratonic basins, including the Baltic, Carpentaria, Illinois, Michigan, Parana, Paris, and Williston basins, indicates that plate tectonic interactions had a major influence on the timing and rates of subsidence, the geometries of the sedimentary sequences, and the development of bounding unconformities.
The origin of interior cratonic basins is unclear. Many are underlain by ancient rifts or aulacogens that appear to have influenced basin development. Those that are not associated with rifts are underlain by crustal inhomogeneities and structures such as interplate sutures and megashears. These intrinsic features coupled with extrinsic forces, appear to have caused episodic subsidence in these basins.
Interior cratonic basins situated in low latitudes during their development were commonly sites for deposition of thick carbonate successions (e.g. Illinois, Michigan, Williston, and Paris basins). In contrast, siliciclastic sedimentation characterized basins that formed in higher latitudes (e.g. Parana and Carpentaria basins).
Highly productive interior cratonic basins are characterized by widespread, mature, organic-rich source rocks, large structures, good seals and a variety of stratigraphic trap configurations. Non-productive basins have one or more of the following: immature source rocks, poorly sealed reservoir rocks, freshwater flushing, and/or complex geology due to numerous intrusions that inhibit mapping of plays.
AAPG Search and Discovery Article #91013©1992 AAPG Eastern Section Meeting, Champaign, Illinois, September 20-22, 1992 (2009)