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The Deadhorse Coulee Member of the Milk River Formation of southern Alberta preserves one of the oldest well-documented non-marine vertebrate assemblages in Canada. In this study, the taxonomic diversity of this member is updated, and vertebrate localities are placed in geographic and stratigraphic context. The stratigraphic provenance of specimens indicates all vertebrate material from this member is latest Santonian (83.5 Ma). A new species of turtle is described. Analyses of the rank and relative abundances of taxa support interpretations of this member as a prograding clastic wedge with localities approximately 40 km from the palaeoshoreline at time of deposition. Results support high local abundances of vertebrates in western North America, with faunal provincialism regulated by distance to the palaeoshoreline and mean annual temperatures. Morphologic changes in small theropod taxa through the latest Cretaceous of western North America act as a case study for evaluating species turnover of vertebrate microfossil material. / Systematics and Evolution

<p> Several sections of the Milk River Formation were measured and studied in detail at Writing on Stone Provincial Park in Southern Alberta. The observed vertical facies succession consists of, from base to top: 1) interbedded, sharp-based sandstones and bioturbated shales; 2) dominantly swaley cross-stratified sandstones; 3) dominantly cross-bedded sandstones; 4) non-marine shales and various thin sandstone and lignite interbeds; 5) local, non-marine cross-bedded sandstones.</p> <p> The sharp-based sandstones have been episodically emplaced on top of offshore muds. The dominantly swaley cross-stratified sandstone is a storm-dominated shoreface deposit in which fairweather deposits (eg. medium scale cross-bedding), are rarely preserved. The cross-bedded sandstones record deposition in tidally-influenced estuaries which cut into beach and shoreface deposits. The section is capped by vertically accreted muds and thin lignite seams which represent floodplain and terrestrial deposition landwards of the strandline. The non-marine cross-bedded sandstones are local representatives of fluvial channel deposits.</p> <p> Paleoflow directions measured in the cross-bedded sandstones indicate that the regional strandline was oriented southwest - northeast at Writing on Stone.</p> <p> Petrographic analysis of the swaley cross-stratified and cross-beddedm sandstones indicate that they are Subarkoses. A definite upward coarsening trend from fine to medium grained quartz is observed in the main sandstone body.</p> / Thesis / Bachelor of Science (BSc)