A nonconformity in which beds above and below are parallel.
An unconformity marked by a distinct erosion-produced, irregular, uneven surface of appreciable relief between parallel strata below and above the break; sometimes represents a considerable interval of nondeposition.
a break in sedimentation with erosion with no deformation so that the upper beds are parallel to the lower
a buried surface of erosion that represents in succession (1) deposition of strata, (2) erosion of some of the strata, and (3) deposition of additional strata.
an unconformity in which the beds above and below an erosion surface are concordant.
An unconformity parallel to the two sedimentary sequences it separates.