Many fluvial point-bar accretion packages show lithological variability, from sand-to mud-dominated. However, the controls on this variability are often poorly constrained. High-quality 3-D seismic data and information from hundreds of wellbores from the Lower Cretaceous McMurray Formation (Alberta, Canada) are employed to characterize the deposits of three point bars and discern the lithological variations amongst and along the length of component accretion packages. Five recurring accretion-package geometries were distinguished: uniform width, wide at apex, narrow at apex, downstream wedge, and upstream wedge. Each of the three point bars was characterized by a breadth of these accretion packages, indicating varied processes during their evolution. The recurrence of accretion packages with consistent geometry and width, however, suggests some consistency and predictability in formative point-bar accretion processes.
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