Definition of unconformity in US English:



  • 1A surface of contact between two groups of unconformable strata.

    • ‘Data on a systemic boundary unconformity on the west Newfoundland shelf are more problematic.’
    • ‘The middle Osagean age of the fauna indicates a previously unrecognized unconformity between the Nada and the overlying Meramecianage Renfro Member of the Slade Formation.’
    • ‘Both overlie a pronounced angular unconformity and both are predominantly fluvial deposits.’
    • ‘First, there are no late Cambrian rocks in many areas: they are represented by unconformities.’
    • ‘That unconformity is overlain by sandstones of the Puentelles Formation, dated as late Kasimovian based on its fossil flora.’
    1. 1.1 The condition of being unconformable.
      • ‘You still get men wearing hats now but it's almost a sign of unconformity for a young man to wear a hat apart from baseball hats.’