Ground-water resources of Cass and Marion Counties, Texas

Cass and Marion Counties, an area of 1,325 square miles in northeast Texas, are underlain by the Cypress aquifer which is composed of the Wilcox Group, Carrizo Sand, Reklaw Formation, and Queen City Sand, all of Eocene age. These geologic units are for the most part hydraulically interconnected and generally function as a single aquifer.