A regional study of the depositional history of the Misty Creek Embayment, Northwest Territories, Canada
The primary objective of this project is to determine the stratigraphic record of the Late Ordovician-Early Silurian(?) Cloudy Formation, within the Misty Creek Embayment. Located in the Mackenzie Mountains, Northwest Territories, Canada, the Misty Creek Embayment is part of a series of horsts and grabens that characterized northwestern Laurentia’s newly formed passive margin in the Cambrian to Ordovician. Two older episodes of rifting are recorded in the embayment, during the Early to Middle Cambrian and during the Early to Middle Ordovician. Based on research with the Geological Survey of Canada in summers 2017 and 2018, I hypothesize the Cloudy Formation records Late Ordovician-Early Silurian(?) rifting. The proposed research entails mapping facies distributions of the Late Ordovician-Early Silurian platformal Mount Kindle Formation, and its transition into the coeval, faulted (?) deep ramp facies of the Cloudy Formation, located within the Misty Creek Embayment. In summers 2017 and 2018, high-resolution (cm-scale) stratigraphic sections were measured with a Jacob’s staff and brunton compass. Sedimentological features include: bedding geometries, sedimentary structures, and faunal content recorded across the ramp. Collected thin section samples will aid in determining depositional environments, which will help determine if faulting caused the Cloudy Formation's anomalous thickness variation. Late Ordovician-Early Silurian deposition of the Cloudy Formation may record a continuation of Middle Ordovician rifting, or constitute a third, separate episode of rifting. Using collected samples from fieldwork, the duration of this rifting event will be determined using δ13C stable isotope chemostratigraphy combined with conodont biostratigraphy.
AAPG Datapages/Search and Discovery Article #90351 © 2019 AAPG Foundation 2019 Grants-in-Aid Projects