Who is responsible? The geologists assemble evidence that correlates the subsidence to the location of the oil wells and the time period of extraction. And they link recent subsidence to continued pumping.

Diagram demonstrating correlation between wells, represented as dots, and subsidence contours, 1926. Solid lines represent subsidence over eight-year period; heavy broken lines show subsidence over a single year. From Wallace E. Pratt and Douglas W. Johnson, "Local Subsidence of the Goose Creek Oil Field," Journal of Geology, October-November 1926. Copyright 1926 University of Chicago. Used with permission of the University of Chicago Press.

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