La Popa basin is located in the folded foreland of the Sierra Madre orogen adjacent to the Monterrey salient of the Sierra Madre Oriental in northeastern Mexico, and contains the Late Cretaceous-Eady Tertiary Difunta Group, a ~5.4km thick succession of synorogenic strata associated with the Sierra Madrean (Laramide-equivalent) orogeny. La Popa basin also contains two diapiric salt stocks and other salt evacuation structures, which were active throughout deposition of the Difunta Group. The Difunta Group was post-depositionally folded over a detatchment, and was syn- and post-depositionally influenced by the development of salt structures; however, the spatial and temporal extent of each influence is unknown. The Cretaceous (Maastrichtian) Muerto Formation, the oldest formation of the Difunta Group, represents the first coarse-grained terrigenous synorogenic influx deposited by an eastward prograding deltaic system sourced from the developing Sierra Madre orogen in the west Excellent exposures of the Muerto Formation adjacent to El Gordo diapir in La Popa basin provide the best opportunity to investigate Muerto/diapir and Muerto/foreland structure interaction. This study will document the facies relationships and stratigraphic behavior of the Muerto Formation with respect to El Gordo diapir and Sierra Madrean foreland structures in southern La Popa basin in order to interpret the evolution of El Gordo diapir and La Popa basin during the Maastrichtian. Investigating the controls of salt diapirism and foreland shortening on sedimentation patterns can be performed using outcrop data; present knowledge is based primarily on remote sensing data. Documentation of facies geometry and stratigraphic data will enhance evaluation of the reservoir potential of sedimentary deposits associated with analogous subsurface settings known only from seismic or bore-hole data. Data from this study can also be employed in calibration of salt tectonic models used in petroleum exploration.
AAPG Search and Discovery Article #90925©1999 AAPG Foundation Grants-in-Aid