The Black Mesa and Kaiparowits Basin area is located in the southwest portion of the Colorado Plateau Structural Province. The Black Mesa basin, encompassing approximately 6400 square miles, extends from the Kaibab upwarp on the west to the Defiance uplift on the east; from the Mogollon Rim on the south to the Utah-Arizona line on the north. The Kaiparowits basin covers approximately 8500 square miles and is bounded by the Sevier and Paunsaugunt faults which delineate the east edge of Basin and Range structures and by the Circle Cliffs upward on the east. To the north the Kaiparowits basin passes under the extensive Tertiary flows of the Aquarius Plateau.

Throughout most of Paleozoic time, the Black Mesa and Kaiparowits basin area occupied an extensive shelf area between the Ancestral Sierra Grande on the east and the Cordilleran geosyncline on the west.

Cambrian, Devonian, Mississippian, Pennsylvanian and Permian sedimentary units are present in the subsurface. No rocks of Ordovician or Silurian age are recognized. Rocks of Permian age and younger are commonly exposed. Paleozoic strata are products of marine sedimentation on the shelf which bordered the Cordilleran geosyncline. Stratigraphic or depositional strike was apparently controlled by adjacent low-lying land masses and embayments into the shelf area from the Cordilleran geosyncline.

Orogenic activity, beginning in Late Pennsylvanian and continuing through the Tertiary affected sedimentation during this portion of geologic time as the seas periodically withdrew and encroached upon the shelf area.

Large anticlinal features are present in both basins which appear to have had an early history and offer many favorable possibilities for oil and gas production in areas of favorable stratigraphy.

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