Rock dating geology

There are situations where it potentially fails -- for example, in cave deposits.In this situation, the cave contents are younger than both the bedrock below the cave and the suspended roof above.his document discusses the way radiometric dating and stratigraphic principles are used to establish the conventional geological time scale.

Cave deposits also often have distinctive structures of their own (e.g., spelothems like stalactites and stalagmites), so it is not likely that someone could mistake them for a successional sequence of rock units. Each of them is a testable hypothesis about the relationships between rock units and their characteristics.They are applied by geologists in the same sense that a "null hypothesis" is in statistics -- not necessarily correct, just testable.In the last 200 or more years of their application, they are valid, but geologists do not assume they are.As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale.To get to that point, there is also a historical discussion and description of non-radiometric dating methods.