Fossil relative dating lab
He also found that certain animals were in only certain layers and that they were in the same layers all across England.
Due to that discovery, Smith was able to recognize the order that the rocks were formed.
There are a number of different types of intrusions, including stocks, laccoliths, batholiths, sills and dikes.
Cross-cutting relations can be used to determine the relative ages of rock strata and other geological structures.
The regular order of the occurrence of fossils in rock layers was discovered around 1800 by William Smith.As a result, xenoliths are older than the rock which contains them.The principle of original horizontality states that the deposition of sediments occurs as essentially horizontal beds.Sixteen years after his discovery, he published a geological map of England showing the rocks of different geologic time eras.Methods for relative dating were developed when geology first emerged as a natural science in the 18th century.