Regional and detailed structural geology of the Quirk Creek structure, S.W. Alberta

Seismic data and surface geology, used in conjunction with borehole data and concepts of structural style are integrated to interpret the complex regional structural geology of the Foothills belt, in addition to the more detailed geometry and along-strike variation of the Quirk Creek structure. The Quirk Creek structure is the northwest extension of the Highwood Thrust sheet. Detailed cross-sections over the Quirk Creek structure illustrate how the geometry of the structure varies along strike from thin imbricates of Mississippian strata in the north to a thick Mississippian thrust sheet containing leading edge folds in the south. The major controls for the structural style and the along-strike variation of the Quirk Creek structure appears to be three-fold: (1) the magnitudes of shortening at the Mississippian and Devonian levels, (2) the stratigraphic position of the controlling detachment, and, (3) the presence of lateral ramps in the Mississippian and Devonian strata.