Paul D. McKinney has been appointed president and CEO of Oklahoma City-based SandRidge Energy. He succeeds William M. Griffin, who will continue to serve on the board. McKinney has 35  years of industry experience, most recently as president and COO of Yuma Energy Inc. He previously worked for Apache Corp. and Tristone Capital, and he began his career in 1983 with Anadarko Petroleum Corp. McKinney has a bachelor of science degree in petroleum engineering.