///In depositional strata, there are mainly two types of unconformities that are the angular unconformity and the leurodiscontinuity. An angular unconformity indicates an obvious tectonic event and a leurodiscontinuity implies a crustal uplift, both of which mark distinct stratigraphic hiatuses. With the rise and broad application of seismic stratigraphy, both the discovery of many stratigraphic terminations within strata and their stratigraphic and sedimentological interpretations led to the emergence of an important and new stratigraphic discipline: sequence stratigraphy. Further, the term “sequence” has been modified to refer to a unit “bounded by unconformities or their correlative conformities”. This new definition made sequence stratigraphy a mainstream of stratigraphic practice.