Four-Dimensional Fold Growth Recorded by Mesozoic-Cenozoic Reefs, Mexican Gulf Coast
D. K. Latta
Lehigh University, Dept. of Earth and Environmental Sciences, Bethlehem, PA
Cyclic carbonate rocks are sensitive recorders of depositional environments, preserving a detailed history of changes in eustasy, tectonism, and sedimentation as reflected in their facies distribution.When associated with growth strata and accessible 3-dimensional exposures, cyclic carbonates represent a powerful tool for establishing high-resolution 3-dimensional deformational histories through time. Syndeformational strata provide the most direct link to structural processes and have been successfully used to date orogenesis, determine the sequence and rates of deformation, and in kinematic studies. A reconnaissance trip to the Sierra Madre Oriental has identified Albian age growth strata on several first order structures wit in the Lower Cretaceous Cupido-Cupidito (Sligo) Fm. cyclic carbonates. Sierra Madre Oriental passive margin sediments are equivalent to the Peridido and Mississippi Fan fold belt stratigraphy, where Upper Jurassic evaporites serve as a regional decollement. Chronologies established from the correlation of high-frequency fourth-and fifthorder depositional cycles within growth strata and the adjacent 112 Ma suspersequence boundary will be used to determine highresolution (~105–104 yrs) rates of deformation and deposition within the evolving folds. The high-resolution 4-D deformational histories determined from meso-scale structures of the Sierra Madre Oriental will help refine the relationships that exist between stratigraphy and structures within thrust belts and get at the allusive deconvolution of eustatic and tectonic controls on Gulf Coast stratigraphy.
AAPG Search and Discovery Article #90902©2001 AAPG Foundation Grants-in-Aid