1. In the image below, lines are drawn to show correlation between the two sections.
2. The section A is the section that contains unconformity.
3. The sandstone and coal were the rock types that were eroded in the Section A.
4. In the image below, we have label the position of the unconformity with an arrow and the word "unconformity.
5. The erosional surface is indicated by the unconformity in section A.
In geography and geology, an unconformity refers to a boundary or contact point between two rock layers or strata that represent a gap in the geologic record. This gap occurs when there is a period of erosion or non-deposition between the formation of the underlying rock layers and the overlying ones.
Unconformities are important because they indicate missing or incomplete parts of the geological history of an area. They can result from processes such as erosion, tectonic activity, or sea level changes.