Lee M. Tillman, most recently vice-president of engineering for ExxonMobil Development Co., has been named president and chief executive officer of Marathon Oil Corp., succeeding Clarence P. Cazalot Jr.
Tillman, a chemical engineering graduate of Texas A&M University with a PhD in chemical engineering from Auburn University, began his career with Exxon in 1989.
Cazalot, who led Marathon Oil for almost 14 years, will retire Dec. 31.