Sanchez Production Partners LLC, formerly Constellation Energy Partners LLC (CEP) is engaged in the acquisition, development and production of onshore oils and natural gas properties in the United States. All of the Company's proved reserves are located in the Cherokee Basin in Oklahoma, the Woodford Shale in the Arkoma Basin in Oklahoma, the Central Kansas Uplift in Kansas and in Texas and Louisiana. The Cherokee Basin is located in the Mid-Continent region in southern Kansas, northern Oklahoma and western Missouri, and covers approximately 26,000 square miles. The predominant production is natural gas produced from coals and shales, and natural gas and oil from conventional formations. The Woodford Shale is located in the Arkoma Basin in southern Oklahoma. The Central Kansas Uplift is an oil-prone region located in Kansas and southern Nebraska.