Clay-Mineral Assemblages in Upper Cretaceous Shales in the Torreon Wash and Star Lake Coal Areas, Southeastern San Juan Basin, New Mexico

摘要

This project was undertaken to characterize the mineralogy and chemical composition of clay mineral assemblages in Upper Cretaceous shales in the southeastern part of the San Juan Basin in northwestern New Mexico and to determine their relations with episodes of coal deposition. The shales represent a range of depositional environments from marine, through near-shore mixed marine and continental, into fluvial and aeolean continental. Coal accumulation in the Torreon Wash and Star Lake areas occurs in both mixed marine and continental and fluvial continental facies.