Rocky Mountain Section - 69th Annual Meeting - 2017

Paper No. 10-7
Presentation Time: 4:00 PM

MIXED DELTAIC, SHOREFACE, AND TIDAL EMBAYMENT SEDIMENTATION ALONG A STORM-INFLUENCED SHORELINE;  OUTCROPS OF THE MOUNT CLARK FM WITHIN THE MACKENZIE MOUNTAINS, NWT


HERBERS, David, Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada and GINGRAS, Murray, Department of Earth and Atmospheric Sciences, University of Alberta, 1-26 Earth Sciences Building, University of Alberta, Edmonton, AB T6G 2E3, Canada, herbers@ualberta.ca

This work documents the presence of siliciclastic early Cambrian Mount Clark Formation shorelines present within the rifted margin of the Mackenzie Depocenter. Three outcrops (Two Lakes, Carcajou Canyon, and Waterfall Ridge) were logged and analyzed for sedimentary and ichnologic content to present an overall facies and stratigraphic framework for the siliciclastic portions of Mount Clark Formation. Observations indicate differing influences of wave/storm and tidal forces in the three localities, each displaying different sedimentary and ichnologic characteristics. In order of decreasing wave/storm and increasing tidal forces the outcrops are as follows: Two Lakes, Carcajou Canyon, and Waterfall Ridge, each having distinct and predictable sedimentologic and ichnologic qualities. Recognizing the differences between tidal and wave/storm influences is key when dealing with basin scale depositional systems. The distribution and scale of sand bodies is significantly different between tidal and wave dominated coastlines (i.e. the presence of a mud filled nearshore deposits landward of the sandy dune deposits). This study documents and describes the sedimentologic and ichnologic characteristics of a wave/storm dominated Cambrian coastline punctuated by tidally dominated protected embayments.