Abstract Green River Formation lacustrine deposits in the eastern portion of Lake Uinta formed in two sub-basins (the Piceance basin and the Uinta basin) and represent mixed siliciclastic-carbonate and organic-rich lake deposits deposited during the Eocene climate optimum. The formation is comprised of organic-rich and organic-poor mudstone, siliciclastics, and carbonates, formed in a shallow to deep (tens of meters), stratified lake environment. Integrated sequence stratigraphic analysis using gamma logs, Fisher Assay plots, core, and outcrop has resulted in a predictive framework for organic-rich oil shale distribution, reservoir characterization, and hydrocarbon systems analysis. Lacustrine strata are characterized by three types of (meter to decimeter) depositional cycles: (1) Type 1 cycles formed in a littoral/sublittoral zones and comprise progradational siliciclastic-rich deposits that pass upward into progradational to aggradational carbonate shoal and microbial carbonate and are capped by mud-to silt-sized sublittoral deposits. In the profundal zone, two types of depositional cycles occur: (2) Type 2 cycles start with lean oil shale, pass upwards into siliciclastic turbidites, and are overlain by rich oil shale deposits. (3) Type 3 cycles initiate with evaporites and mixed lean and rich oil shale that is overlain by rich oil shale. Stacked depositional cycles form depositional sequences meters to tens of meters thick. Eleven upward-deepening depositional sequences have been described and are divided into periods of low, rising, and high lake that are separated by sequence boundaries, transgressive surfaces, and main flooding surfaces, respectively. The development of depositional cycles and sequences in these lacustrine basins appear to be strongly affected by climate changes and respective inflow; i.e., during times of low inflow (low lake level) siliciclastic and nutrient input into the lake decreased. In contrast, the highest input of siliciclastics and nutrients occurred during increased and high inflow (rising and high lake level). Low lake level is marked by thin marginal deposits and lean oil shale and at times, evaporite deposition in profundal areas. Increased runoff is marked along basin margins by sharp-based sandstones and carbonates. In the profundal area, rich oil shale overlay lean oil shale.

Ferdinand Hayden's 1868 survey of the Wyoming and adjacent territories was a small, largely ignored survey; but it was important to the history of geology and the American West. The discovery of new material related to Hayden's 1868 survey, including a personal diary of one of the assistants on the survey, James Carson, provides critical information that allows the survey's story to be fully articulated and analyzed for the first time. Most of the expedition's activities took place in southern Wyoming and were closely intertwined with one of the most noteworthy events in U.S. history—the building of the transcontinental railroad. The railroad's construction activities caused Hayden to have serendipitous encounters with legendary army generals, businessmen, politicians, photographers, geologists, and thieves, many of whom significantly changed the course and scope of the survey. Some of these people included James Hall, General John Gibbon, Frank Blair, Louis Agassiz, Thomas Durant, and William Gilpin. Despite severe underfunding and the lack of a military escort, the survey persevered and surpassed its original goals. It produced the first descriptive stratigraphic-structural profile across the Rocky Mountains from Cheyenne to Salt Lake City and, somewhat unknowingly, the first documentation of dinosaur tracks in western North America. The overall success of the expedition allowed Hayden to expand his surveys and helped solidify his reputation as an important pioneering American geologist. However, the field reports of the survey and Hayden's zeal to appease important people may have helped to prevent his hoped-for appointment as the first director of the U.S. Geological Survey.