Large-scale cross-stratification is present in the St. Peter Sandstone of southern Wisconsin. Sets of cross-bedding are as much as 35 ft thick and are made up of thick master fore-set units which contain sets of smaller scale, internal cross-stratification. The master fore-set units occur as two types of cross-stratification: convex upward, planar and convex downward, tangential. Both the large-scale master fore-set bedding and the small-scale internal fore-set bedding dip toward the southwest, parallel to the regional paleocurrent pattern. The large-scale cross-stratification in the St. Peter Sandstone is the result of internal structures developed in large migrating sand waves, dunes, banks, or ridges.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.