Radiometric dating

07 Jun

"Near the end you imply that low petrologic type chondrites are the most easily dated.Actually, meteorites that formed by melting, e.g., the various types of achondrites, usually give more precise Tas Walker A geologist works out the relative age of a rock by carefully studying where the rock is found in the field.

There are some things that affect these measurements.

For example, a geologist may examine a cutting where the rocks appear as shown in Figure 1.

Here he can see that some curved sedimentary rocks have been cut vertically by a sheet of volcanic rock called a dyke.

Clearly, Sedimentary Rocks A were deposited and deformed before the Volcanic Dyke intruded them.

These were then eroded and Sedimentary Rocks B were deposited.