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Farnsworth Unit (FWU) is the site of one of the first commercial-scale carbon capture, utilization, and storage (CCUS) projects in the United States. The purpose of this study is to better understand how the depositional environment and diagenesis of the upper Morrow sandstone affect reservoir heterogeneity and the potential for residual CO2 trapping in FWU. We build upon previous studies of the petroleum geology of the unit using interpretations of the depositional environment that place the unit in a sequence stratigraphic context, and present new core, petrographic, and geochemical data. Lithofacies in FWU core are consistent with the regional incised valley model of deposition. The coarse-grained reservoir sandstone is interpreted to be fluvial. It is underlain by channel lag conglomerate and marine mudstone and overlain by fine-grained estuarine sandstone and marine mudstone. Reservoir quality does not appear to be controlled by primary depositional features, such as grain size and sorting. Diagenetic (secondary) processes had a much greater effect on the reservoir quality of the upper Morrow sandstone than depositional processes. Petrography reveale