HOUSTON, Jan. 15, 2014 /PRNewswire/ -- EnerVest, Ltd., today announced that Ken Mariani has been named President of the Company. John B. Walker, founder of EnerVest, will retain the position of Chief Executive Officer and also will continue as Executive Chairman of EV Energy Partners, L.P. (EVEP). In this capacity, Walker will focus his daily efforts on acquisitions, institutional fundraising, EVEP and strategic planning. In addition, the Company announced that Stephen McDaniel has been named President and CEO of EnerVest Operating Company, and Jud Walker has been named Executive Vice President and COO of EnerVest Operating Company. As President of EnerVest, Ltd., Mariani will have day-to-day management responsibility of the Company. Initially, Ken will be more involved with the Company's acquisitions efforts and continue to provide focus on EnerVest Operating Company and Planning and Analysis. "Ken's leadership skills have enhanced our operations and provided strong direction for our employees," Walker said. "We are blessed to have a strong management team, and I look forward to working closely with Ken in his new role." Mariani joined the EnerVest family in 2000 and most recently served the Company as Executive Vice President of EnerVest, Ltd., and President and CEO of EnerVest Operating Company. Prior to that he was Senior Vice President and General Manager – Eastern Division – for 11 years. From 1991 to 2000 he served as Vice President of Operations for Energy Corporation of America (ECA), and was responsible for Engineering, Land, Geology and Production operations. Prior to his role at ECA, he held various engineering positions at Conoco, Inc., in the Midland, TX, and Rocky Mountain Divisions. Mariani holds a degree in Chemical Engineering from the University of Pittsburgh, graduating cum laude with a Petroleum option. He earned his Master of Business Administration from the University of Texas (Permian Basin) and is a Licensed Professional Engineer. He is an active member of various Independent Oil and Gas Associations, and recently served on the Board of Directors in the Michigan, Ohio and West Virginia associations. He is past Chairman of the Appalachian Chapter of the Society of Petroleum Engineers and is a member of the Independent Petroleum Association of America. Prior to being named to his new position, McDaniel served as Executive Vice President and COO of EnerVest Operating Company. Prior to that he served as Senior Vice President and General Manager – Western Division, and also ran the acquisition and divestiture group for EnerVest where he was responsible for more than $1 billion in acquisitions and more than $400 million in divestitures. Before joining EnerVest in 2000, McDaniel worked for Santos USA Corp., Coastal Oil & Gas Corporation and OXY USA Inc. in reservoir and operations engineering positions of increasing responsibility. He earned a Petroleum Engineering degree and a Master of Business Administration from the University of Oklahoma. McDaniel is a member of the Society of Petroleum Engineers, the Independent Petroleum Association of America and the Houston Producers Forum.