How rock layers in different locations can be connected to make pictures of a region's geology.
A sample of volcanic ash is used to demonstrate leaf fossils in lapilli tuff. Learn how the distinctive texture of the volcanic rock and the included fossils can be used to help correlate it with other volcanic rocks in the region.
Reviews how rock units in different locations can be correlated to understand the geology of a region.
The John Day Fossil Beds in eastern Oregon have a weath of fossils that span a long period of time. The relative ages are well constrained becauase a volcanic ash has been radiometrically dated.