Cross-stratification is a sedimentary structure that occurs from migrating ripple (smaller-scale) or dune (larger-scale) laminae and bedforms due to current flow processes in various environments, such as fluvial, eolian, lacustrine, or marine. Sedimentation causes an inclined foreset in which mobile grains are carried over the stoss and ultimately deposited onto the lee-side, which then migrates with the horizontally deposited bottom-set. This migration results in the truncation of sedimentary layers, known as cross-stratification. These structures can also be indicative of the direction of paleocurrents in that flow from stoss to lee-side. This sample is an excellent example of unidirectional flow. Cross beds are distinguished from each other by the shape of their bounding surfaces. When the bounding surfaces appear to be planar and 2-dimensional, the bed is a tabular cross-bed. Meanwhile, if the bounding surfaces appear to be curved and dimensional, it is called a trough cross bed. The upper annotated portion of this sample is an example of well-defined tabular cross-bedding.