Several intersecting multichannel seismic lines shot by The University of Texas Marine Science Institute in the deep Gulf of Mexico provide a three-dimensional grid in the vicinity of Challenger Knoll. Seismic stratigraphic sequences identified on the lines include the Sigsbee, Cinco de Mayo, Upper and Lower Mexican Ridges, Campeche, and Challenger units. Isotime

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maps document a detailed growth history of the Challenger diapir. DSDP drill holes 2, 3, and 87 provide age data for the grid.

Differences in the style of diapirism between the northern (Louann) salt province and the Sigsbee salt province to the south are due to the influence of the basement. Both the original distribution of evaporites and subsequent diapirism in the vicinity of Challenger Knoll are controlled by basement fault blocks of transitional crust that formed during the initial opening of the Gulf of Mexico.

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