Answer:
Unconformity
Step-by-step explanation:
In geology, unconformity is an erosive surface that separates two sedimentary rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the oldest layer was exposed to erosion for a period of time before the new deposition, but the term is used to describe any rupture in the geological sedimentary record. The meaning of angular unconformity was shown by James Hutton, who found examples of disagreement at Jedburgh in 1787 and at Siccar Point in 1788.