BEDROCK GEOLOGIC MAPPING OF THE COW HEAD PENINSULA IN NEWFOUNDLAND, CANADA AIDED BY GEOCHEMICAL ANALYSES AND GEOPHYSICAL SURVEYS

Prior mapping on the Cow Head Peninsula in Newfoundland, Canada focused on the stratigraphy and paleontology of shoreline exposures of the late Cambrian to early Ordovician age Shallow Bay Formation. However, minimal structural data was collected and the densely vegetated interior of the peninsula was not adequately mapped, resulting in an incomplete geologic assessment of the area. Further, the limited structural data collected (only bedding/contacts and major faults) make it difficult to conduct quality structural analyses that can aid in understanding the kinematics of the region. The Shallow Bay Formation primarily consists of massively bedded limestone conglomerates and finely bedded micrite with interbedded shale that deposited at the base of continental slope environment situated between the Laurentian continent and the Iapetus Ocean. Prior research subdivided the formation into four distinct members: Downes Point, Tuckers Cove, Stearing Island, and Factory Cove. Reconnaissance fieldwork completed in 2019 identified inconsistencies in the named members and structural features, particularly along the southern shoreline. This discrepancy may be in part due to the similar lithology of several map units established by prior researchers. Our research overcomes many of these challenges and clarifies the bedrock geologic map by: (1) reassessing the subdivisions of map units to limit thickness variability for mapping purposes, (2) using geochemical datasets (carbonate stable isotopes) as a tracer to aid in the identification of interior units for mapping, (3) incorporating structural data of weathered exposures in the interior of the Peninsula where possible, geochemical analyses and microscopy to aid in the identification of said exposures, and geophysical surveys to confirm fault traces across the peninsula, (4) providing an analysis of the many and varied structural data collected, and (5) producing a detailed bedrock geologic map of the Peninsula in its entirety. Results from this project will yield new insights into the complex geologic and tectonic history of the Northern Appalachian Orogenic Belt.