🔥 Haynesville Shale

The Haynesville Shale is an informal, popular name for a Jurassic-Period rock formation that underlies large parts of southwestern Arkansas, northwest Louisiana, and East Texas. It lies at depths of 10,500–13,000 feet (3,200–4,000 m) below the land’s surface. It is part of a large rock formation which is known by geologists as the Haynesville Formation. The Haynesville Shale underlies an area of about 9,000 square miles (23,000 km2) and averages about 200–300 feet (61–91 m) thick. The Haynesville Shale is overlain by sandstone of the Cotton Valley Group and underlain by limestone of the Smackover Formation.