LiDAR assisted mapping and deformation history of Crowsnest Pass, Alberta

Abstract

The Crowsnest Pass area, located in the Rocky Mountain foothills of the Canadian Cordillera, provides an exceptional example of a thin-skinned thrust belt from which the deformational history can be determined. Use of LiDAR (light detection and ranging) data, acquired by high-resolution remote sensing, increased both area covered in the field and accuracy. An anticline cored by Paleozoic carbonate rocks in the hanging wall of the Turtle Mountain thrust, established from a revised geological map and cross-sections, is a fault-propagation fold. Strain analysis, by both Fry and calcite strain gauge methods, shows that deformation was heterogeneous and involved volume loss. The kinematic model that best matches the deformational history of the fold involves both volume loss and deformation along a thrust that was initially localized at one or more nucleation segments and then propagated through adjoining layers.