| Summary: | Degree: Master of Science Abstract: The early Cambrian Mount Clark Formation of the Northwest Territories comprises marginal marine to marine siliciclastic sediments deposited in an incipient rift basin on the margin of Laurentia. Within core and outcrop datasets the preserved record of sedimentation represents complex and highly variable lateral to vertical architecture. As a result of recording early Cambrian (Series 2, Stage 3: Bonnia-Olenellus trilobites) the Mount Clark Formation represents a rare opportunity to study marine biological interactions at the very onset of the Cambrian Explosion. To achieve this objective, high resolution sedimentological ichnological data was recorded from a six core database within the Colville Hills in addition to the field description of 8 outcrops in the Mackenzie Mountains over the course of two field seasons. Eight distinct lithofacies (F1-F8) were identified in the Colville Hills recording offshore to continental deposition along a strongly storm-influence shoreface succession. Three distinct facies associations (FA1-3) were identified within the Mackenzie Mountains recording shoreface (FA1), deltaic (FA2), and tidal embayment (FA3) sedimentation. Shoreface sedimentation (FA1) ranged from strongly storm-influenced to storm-affected lower shoreface to foreshore environments and were identified on the presence of robust and diverse trace fossil assemblages. Deltaic sedimentation (FA2) ranged from strongly storm-influenced to storm-affected prodelta to upper delta-front environments and were identified on the basis of stressed trace fossil assemblages recording decreasing ichnofossil size, diversity, and abundance in collaboration with more immature lithologies. Tidal compound dune sedimentation (FA3) ranged from embayment margin to the core of a compound dune field. Shoreface trace fossil assemblages within both study areas were found to have higher degrees of diversity, abundance, and complexity than previously identified early Cambrian trace fossil assemblages. It is ...
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