Chaparral Energy searches the scrublands of America's Mid-Continent and Permian Basin, looking for oil and natural gas. The exploration and production subsidiary of Chaparral Energy Inc. also drills in North Texas, the Gulf Coast, the Ark-La-Tex region, and the Rocky Mountains. It has proved reserves of some 158.1 million barrels of oil equivalent. Some of its reserves are in enhanced oil recovery project areas, primarily in Oklahoma and Texas, where the company uses carbon dioxide (CO2) to flood wells to release trapped oil in mature and well-worked fields. Securing CO2 supply from third party plants is key to its enhanced oil recovery. The company filed for bankruptcy protection in 2016.