Western Geophysical was a company founded in California in 1933 by Henry Salvatori for the purpose of using reflection seismology to explore for petroleum. The company prospered and was sold by Salvatori to Litton Industries in 1960. In 1987, Litton and Dresser Industries formed a joint venture comprising Western and Dresser Atlas. The joint venture, Western Atlas, was spun off as a public company in 1994. Western then purchased Halliburton Geophysical Services, which had been formed from Geophysical Service Incorporated, Geosource and several other companies. In 1998, Western Atlas was acquired by Baker Hughes. In 2000, Western Geophysical became part of a joint venture between Baker Hughes and Schlumberger called WesternGeco and ceased to exist as a separate entity. In May 2006, Schlumbe