| Summary: | Replacement matrix dolomite (RMD) is present throughout the Leduc/Cooking Lake Formation, but is restricted to the bank margin in the Swan Hills Formation. RMD has an average crystal size of 140$ mu$m and fluoresces yellow in the Leduc/Cooking Lake Formation but has an average crystal size of 250$ mu$m and fluoresces green in the Swan Hills Formation. RMD formed before the onset of stylolitization. It has abundant inclusions, a homogeneous red cathodoluminescent response, and similar trace element concentrations in both formations. $ delta sp{18}$O values overlap for the most part, but some Swan Hills dolomites are 1 to 2$ perthous$ lighter in $ delta sp{18}$O. The Leduc/Cooking Lake dolomite has a slightly greater range in $ delta sp{13}$C, with several samples lighter than +1.5$ perthous$. Diagenetic fluids derived from seawater are supported by average $ delta sp{13}$C, $ delta sp{18}$O (1.77$ perthous$, $-$4.19$ perthous$; 2.81$ perthous$, $-$4.95$ perthous$), and $ sp{87}$Sr/$ sp{86}$Sr (.7082;.7086) values in the Leduc/Cooking Lake and Swan Hills dolomite respectively. Yellow fluorescence and pyrolysis parameters in the Leduc/Cooking Lake dolomite could be caused by the presence of mature organic compounds.
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