Trough cross-stratification is the most abundant, accurate, and efficient paleocurrent-direction indicator in fluvial deposits. However, exposures in which trough axes can be measured are rare. Two methods are presented for the determination of paleocurrent directions from the more common exposure types; the use of three-dimensional exposures of oblique cuts through individual trough limbs, and two-dimensional exposures of sets of trough cross-strata. Three-dimensional exposures of trough limbs can be measured and treated statistically on a stereographic plot to determine the average trough-axis orientation. In two-dimensional exposures, characteristic asymmetry of the basal scour surface and truncation of foreset laminae can aid in estimation, within about 25 degrees , of paleocurrent direction.--Modified journal abstract.

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