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Major Tectonic Elements of the Midland Basin Defined by Structure on
Top of the Yates Formation


structuremap
Tectonic elements that controlled depositional facies and salt dissolution in the Midland Basin. Structure contours on the top of Yates Formation modified from Geomap, 1986.

The structure on the top of the Yates Formation shows the sum of all the post-Guadalupian deformation in the study area, the net result of Permian subsidence, Mesozoic warping, and Cenozoic uplift. Facies in the Yates Formation siliciclastic red beds indicate that it was deposited over the entire area at near sea-level elevation, as controlled by the water table. The geometry of widespread anhydrite beds in the Salado Formation above the Yates support the concept that the Yates was deposited over a low-relief surface. However, in the Delaware Basin, the Bell Canyon was deposited on the basin floor. This surface may also have been fairly low relief but was at an elevation of as much as 1,000 ft below sea level at the end of the Guadalupian.

At present, in the structural center of the Midland Basin, the top of the Yates Formation, lies at 500 ft below sea level. East of the axis of Midland Basin, the top of the Yates Formation rises toward elevations of 2,000 ft above sea level in the Permian outcrop area on the Rolling Plains. Several areas of anomalous structure are noted within the Midland Basin: an isolated uplift in Reagan County; a closed depression in Midland County; and several uplifts and a depression at the Howard-Glasscock High. The top of the Yates also rises to 1,500 ft at the Matador Arch that defines the north edge of the Midland Basin. Elevation of the Yates Formation rises abruptly over the Central Basin Platform on the south and east edges of the Midland Basin, reaching 1,000 ft above sea level over the north part of the Central Basin Platform and 1,800 ft above sea level in the south edge of the Central Basin Platform. The complex pattern of uplifts that defines the structure of the Central Basin Platform and creates numerous structural traps is apparent even in the generalized regional view shown.

Geologic Setting
Outcrop Geology: Generalized Geologic Map
Depth to Salt: Alibates — Surface Isopach
Above Salt Structure: Structure on Top of the Alibates
Thickness of Salt-Bearing Interval: Ochoan Isopach
Salt Quality: Net Salt and Percent Salt