How Geologists Interpret Ancient Environments. 2 Ruffles and desiccation
Nearly all sedimentary rocks contain structures – fabrics, planes, contortions. If properly identified these sedimentary structures provide important clues to how the original sediments were deposited.
There are many different kinds of sedimentary structures formed by layers of sediment oriented at different angles, or layers that have been contorted and squished, structures formed by wetting and drying of sediment, structures formed by slip and slide, and by animals leaving tracks and traces as evidence of their activity.
All of these structures can be thought of as contributing to the architecture of sediments and sedimentary rocks.
We are going to examine two of the more common kinds of sedimentary structure – Ripples, and Mud Cracks (sometimes called Desiccation Cracks).