Union Oil Company of California. Union Energy Mining Division. Casper (Wyo.) Office.

The Union Oil Company of California (later known as Unocal) was founded in 1890. The Minerals Exploration Company was a wholly owned subsidiary of the Union Oil Company of California. In 1979, all of the company's energy mining operations (including the Minerals Exploration Company) were consolidated into the Union Energy Mining Division. The central region office of this division was based in Casper, Wyoming and was responsible for the exploration and acquisition of coal and uranium. Offices in Casper closed in the mid-1990s.

From the guide to the Union Oil Company of California. Union Energy Mining Division. Casper (Wyo.) Office mineral exploration records, 1914-1995, 1950-1985, (University of Wyoming. American Heritage Center.)