Clarence P. Cazalot Jr. is chairman, president and chief executive officer of Marathon Oil Corporation and a member of the Marathon Oil Corporation Board of Directors. He joined Marathon in March 2000.

Immediately prior to this, Mr. Cazalot served as vice president of Texaco Inc. and president of Texaco's worldwide production operations. He was appointed president of Texaco's worldwide production operations in 1999.

From January 1998, Mr. Cazalot served as president of international production and chairman of London-based Texaco Ltd. He was named president of Texaco International Marketing and Manufacturing in January 1997.

In 1994, Mr. Cazalot was appointed president of Texaco Exploration and Production Inc. in Houston, Texas. Prior to this, in 1992, he was elected a vice president of Texaco Inc. and president of Texaco's Latin America/West Africa Division based in Coral Gables, Florida.

Mr. Cazalot was appointed general manager of the Texaco frontier exploration department in Bellaire, Texas, in 1987. In 1985, he was named assistant to the vice chairman. He was appointed staff geologist for the exploration and production executive committee of Texaco Inc. at the company's executive offices in White Plains, New York in 1984.

Mr. Cazalot joined Texaco in 1972 as a geophysicist in Bellaire, and transferred to the company's offshore division in New Orleans, Louisiana, in 1974. He subsequently held a number of posts of increasing responsibility before being named assistant district geologist in 1976, district geologist in 1977, assistant division geologist in 1979 and regional manager of exploration in 1981.

Mr. Cazalot is a native of New Orleans and graduated from Louisiana State University with a bachelor's degree in geology. In May 2007, he was awarded an Honorary Doctorate of Humane Letters from Louisiana State University.

He serves on the Boards of Directors of Baker Hughes Incorporated, the American Petroleum Institute, the LSU Foundation and the Greater Houston Partnership. He serves on the Advisory Board of the World Affairs Council of Houston and the James A. Baker III Institute for Public Policy. He also serves on the Board of Visitors of the University of Texas M.D. Anderson Cancer Center, the Executive Advisory Board of the Houston Minority Supplier Development Council and the board of the Bipartisan Policy Center Energy Project.

Mr. Cazalot is also a member of the Business Roundtable (BRT), the American Association of Petroleum Geologists, the National Petroleum Council and the All-American Wildcatters organization.