Realative dating age of rocks updating the bios for a new power supply
This principle has in the meanwhile been established to be true for all sediments worldwide, and is the basis of worldwide correlation of sedimentary rock units and one of the underpinnings of the theory of evolution. In location A we have rock layers that successively have different types and combinations (assemblages) of fossils.
If in location B we find the same fossil assemblage (Assemblage 2) in a rock unit, we may assume that they are of essentially the same age as in location A.
If archaeologists find a site with layers in it, they can make assumptions about the relative age based on the composition of materials in each layer.
For example, if an area used for trash has modern refuse in it such as CDs and computers, and the layer underneath has cans made of tin, then it is safe to say the layer of tin cans have a greater relative age than the layer with modern refuse.
Conversely, the igneous rocks are younger than the sedimentary rocks.