- GeoRef, Copyright 2008, American Geological Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
Statistical Markov chain analysis applied to vertical lithic transitions demonstrates cycles (average 30 feet thick) in Paleocene alluvial sediments of the Polecat Bench Formation in the northern Bighorn Basin, Wyoming. Subtracting the independent trials probabilitymatrix from the transition probability matrix leaves a residual matrix of positive probabilities that define the fully developed cyclothem. The fully developed cyclothem for the Polecat Bench sequence is the succession sandstone-mudstone-limestone-mudstone-lignite.