Overstep
From Wikipedia, the free encyclopedia
An overstep is a geological form that has a deposition of a stratum across inclined, progressively older rocks.[1]
The Indira Gandhi National Open University syllabus definition is: "The term overstep is used to describe the relationship of beds in an unconformable sequence where the younger series rests upon progressively older members of the underlying series."[2]
An onlap is a more general term than overstep, in which the younger beds overlap onto successively older beds.
