Home | Session 3 | Sedimentary Rock Pg 1, 2, 3, 4, 5, 6, 7, 8, 9

What's in a Sedimentary Rock?

Presented by Carol Tang
California Academy of Sciences

 

	Thin section of Jurassic-age ooid carbonates (Carmel Formation, Utah). These grains are ooids. They are rounded because they have been turned over and over by waves and tides. (Slide is 2.6 mm across)
	Outcrop of fossiliferous Missippian-age carbonate (Tin Mountain Limestone, Funeral Mountains). This slide shows that fossil material (crinoid fossils) can be a large component of sedimentary rocks.
	Modern mudcracks. Formed when muds dry out and the crust cracks in a very typical fashion. Using modern forms, we can interpret the geological record.
	Precambrian mudcracks (Arizona). Although these are hundreds of millions of years old, they exhibit the same characteristics of modern mudcracks and this suggests that they were formed by the same processes as the modern ones.

Top Next Page

updated February 11, 2002

UCMP Home  |   What's new  |   About UCMP  |   History of Life  |   Collections  |   Subway