Geophysical Service

This article's tone or style may not reflect the encyclopedic tone used on Wikipedia. See Wikipedia's guide to writing better articles for suggestions. (February 2024) (Learn how and when to remove this message)

Geophysical Service Inc.

Founded	1930
Headquarters	Dallas, Texas, U.S.
Website	www.geophysicalservice.com

Geophysical Service Inc. (often abbreviated GSI) was a Texas-based company founded by John Clarence Karcher and Eugene McDermott in 1930,^[1] for the purpose of using refraction and reflection seismology to explore for petroleum deposits.