Abstract
Relief on a prograding clastic complex is used to estimate the water depth of Eocene Lake Uinta in the Piceance Creek Basin of western Colorado. Relief of as much as 412 in is present today on the complex. Postdepositional compaction can account for only about 100 m of this relief; therefore, the remaining 312 m appear to represent paleorelief on the floor of Lake Uinta—the lake was apparently more than 300 m deep. Authigenic saline minerals were precipitated in the unlithified sediments of the deeper areas of the lake, suggesting that at least the lower part of the water column was highly saline. The evidence presented here indicates that the deep stratified lake model is more appropriate than the more generally accepted shallow or playa-lake model for Lake Uinta.
