The St. George Basin, Alaska, COST #1 Well: An Example of the Need for Integrated Interpretation
David A. Chapin, SubbaRao V. Yalamanchili, Paul H. Daggett, 1998. "The St. George Basin, Alaska, COST #1 Well: An Example of the Need for Integrated Interpretation", Geologic Applications of Gravity and Magnetics: Case Histories, Richard I. Gibson, Patrick S. Millegan
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The 1976 St. George Basin COST #1 well, Bering Sea, Alaska, produced unexpected results. Twenty oil companies participated in the drilling of this expensive stratigraphic test, and the well was expected to encounter a thick nonigneous sedimentary section in the deepest portion of the basin. Instead, the well drilled through more than 1000 m (3300 ft) of Tertiary basalt and other volcanic extrusives before it was abandoned. Gravity and magnetic data were available before the well site was chosen, but the information apparently did not impact the site selection. A recent reexamination of the data available in 1975 reveals that significant gravity and magnetic anomalies occur over the well site. These data point to an interpretation that the St. George COST #1 well is located on a collapse feature associated with an igneous calderalike structure. The experience gained from this well demonstrates the need to integrate all available types of data prior to making exploration decisions.