Depositional modeling and interaction between lithofacies assemblages of Cretaceous-Paleogene strata of the Raton Basin

Abstract

The Raton Basin of Colorado and New Mexico is a Laramide foreland basin that has been important to coal geology since its first identification as a coal resource in 1821, and as a major Coal Bed Methane resource in the modern era. The interaction between the lithosomes assemblages of strata within the Raton Basin is not fully understood. This work utilizes well log correlations, core descriptions, measured sections, and digital outcrop models to create paleogeographic reconstructions of the Raton Formation depositional systems. The coaly, fine-grained rocks of the lower and upper coal zones of the Upper Cretaceous to Paleogene Raton Formation are indicative of deposition in a wet, channel-floodplain environment with intermittent periods of basin scale lacustrine flooding. The coarser, sand-rich barren series of the Raton Formation displays a fan shape geometry with abundant terminal splay and channel form lithofacies suggesting deposition within the medial to distal zone of a distributive fluvial system.