Two layers of rock contain fossils of the same kinds of trilobites; however, one rock layer is a shale and the other is a limestone. Can these two layers be used for correlation?

Correlating Shale and Limestone Layers Containing the Similar Trilobite Fossils

Correlation is a elementary device utilized in geology to find out the age of rocks and to grasp the stratigraphic relationships between two or extra rock layers. Correlation is achieved by evaluating the fossils present in every layer and trying to determine similarities between them. On this case, two separate rock layers, a shale and a limestone, have been discovered to comprise fossils of the identical kinds of trilobites. Can these two rock layers be used for correlation? The reply is sure, however with a number of caveats. A very powerful of those is that the rock layers should be contemporaneous (Lüning, 2019). In different phrases, they will need to have been laid down on the similar time in the identical surroundings. If that is so, then the 2 rock layers can be utilized to realize an understanding of the age and stratigraphic relationship of the 2 layers. Moreover, the fossils should be of the identical species, as variation between species of trilobites can point out totally different environments or ages (Chen et al., 2015). In conclusion, shale and limestone layers containing the identical trilobite fossils can be utilized for correlation.