The Sedimentology, Stratigraphy and Structural Geology of the Carswell Formation, Northern Saskatchewan
Date
1985-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Degree Level
Masters
Abstract
The Carswell Formation dolostone is the uppermost unit of the Proterozoic Athabasca Group, located in northern Saskatchewan, Canada. The formation is approximately 500 m thick, and has been faulted and folded into a circular outcrop pattern. The formation consists of stromatolites, laminated and massive mudstones, intraformational conglomerates and breccias and oolitic lenses, all of which are indicative of a shallow marine depositional setting. Desiccation cracks are common. A statistical analysis of the stratigraphic sequence shows no repetitive or cyclical patterns among the different rock types. The formation may be divided into seven units, each representing a different depositional setting. The first four units represent stages in a shallowing-upwards sequence in an agitated environment, whereas the three upper units represent intertidal sediments deposited in a quieter, more protected environment.
The dolostones were mapped at a scale of 1:20,000, and stratigraphic sections were measured through the formation at five different localities.
The stratigraphic sequence through the Athabasca Group is similar to that of
the rocks in the Thelon Basin in the N.W.T. The structural history of the dome is complex. The
dolostones were deposited in a slowly subsiding basin and were subject to continuous tectonic activity. NE-SW and NW-SE trending faults were common, with associated minor
folds. At approximately 480 Ma, the dolomites were rotated to the near vertical and arcuately faulted. After this major tectonic event, known as the Carswell event,
the original fault patterns were reestablished. No shock metamorphic features are evident in the dolomite. The formation may have been deposited in a structurally con-
trolled basin, its original size possibly not much more extensive than what exists today, or it may have been deposited over a wider area and was preserved by downfaulting during the Carswell event.
Description
Keywords
Citation
Degree
Master of Science (M.Sc.)
Department
Geological Sciences
Program
Geological Sciences