Three prominent faults cut the complexly-deformed rocks of the Beaverlodge area, Saskatchewan. These are the Black Bay, the St. Louis, and the ABC Faults. The Black Bay strikes northeast and dips to the southeast. The St. Louis, with a similar attitude, lies a few miles southeast of the Black Bay and, as traced southwestward, bends gradually toward the other fault. At a point where the two faults are about 3.5 miles (5.5 km) apart, a third fault runs between these two breaks. This third fault, the ABC, strikes northwest and dips southwest.A study of major and minor fractures along the ABC Fault indicates a left-hand, normal oblique movement for the fault. This evidence combined with the stratigraphic separation of the Martin Formation across the fault, gives a net slip for the ABC Fault of 12 × 103 ft (3.7 × 103 m). The southwest side moved down and southeastward relative to the northeast side.Movements on faults in the area imply two main orientations of principal stresses. These orientations apparently occurred at different stages in the uplift of a northeast-southwest elongated dome.

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