UNCONFORMITIES ARE THE RECORD OF MAJOR EPISODES OF UPLIFT, EROSION AND SUBSIDENCE DURING THE GROWTH OF THE CONTINENTS AS EARTH HISTORY PROGRESSED. THEY ARE THEREFORE IMPORTANT EVIDENCE FOR CRUSTAL MOBILITY THROUGHOUT EARTH HISTORY.

What do unconformities represent?

An unconformity is a surface between successive strata that represents a missing interval in the geologic record of time, and produced either by: a) an interruption in deposition, or b) by the erosion of depositionally continuous strata followed by renewed deposition.

What does a geologic unconformity indicate?

An unconformity represents time during which no sediments were preserved in a region or were subsequently eroded before the next deposition. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area.