DAVID
L.
The Paradox basin has been heavily investigated for its reservoir potential, though explicit models for the development of the basin are few. Preliminary analysis of basin morphology and facies relationships support a flexural interpretation of its development. Published isopach data of the asymmetrical and NW-trending evaporite-dominated basin indicate a basin-parallel trend stratigraphic thins about 210 km SW from the basin-bounding Uncompahgre uplift. Coincident with this trend is the biohermal facies of the Desmoinesian Paradox formation, which maintains a lateral and correlatable relationship with the cyclic evaporite sequences in the deepest parts of the basin to the NE. To the SW of these bioclastic mounds, the basin thickens again. These stratigraphic thins and thicks are interpreted to be the forebulge and back-bulge depozones (respectively) of a flexural foreland basin system. Flexural modeling describes deflection of a broken-plate crust with an elastic thickness of 25 km (flexural rigidity of 1023 Nm) by an estimated Uncompahgre load that correlates well with a basin profile constructed from restored stratigraphic units.
Current research pin-points the depozones of the proposed flexural basin through comprehensive stratigraphic section-measuring and well-log correlation. An explicit flexural model for the Paradox basin has implications for Ancestral Rocky Mountain tectonics and the general development of flexural basins that result from Laramide-style uplifts. The correlation between the forebulge depozone and the hydrocarbon-abundant bioherm facies makes our understanding of such foreland systems additionally important.
AAPG Search and Discovery Article #90925©1999 AAPG Foundation Grants-in-Aid