Chemostratigraphic Results of Cretaceous Eagle Ford Formation, South Texas

Cenomanian/Turonian-age strata of the Eagle Ford Formation, south Texas, can be largely characterized as carbonate-rich mudrocks and limestones. Here, their chemostratigraphic compositions are compared and interpreted in the context of changing depositional environments and the potential for linking the records to well-logs. We focus on core chemostratigraphies from La Salle, Zavala, Guadelupe, Gonzalez counties. High %Ca and a strong linear relationship between %Ca and %TIC (total inorganic carbonate) indicates that the Eagle Ford in the core areas is overwhelmingly composed of calcite. Furthermore, the strong linear relationship between %Al and %Si indicates that there is relatively little quartz content, and that the silica is dominantly in the clay phase. Stable carbon and oxygen isotopic (δ¹³C and δ¹⁸O) results for cores will be discussed as a tool for correlation and for defining discrete stratigraphic zonation in each core.

AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California