Applications of parasequences and lithologic zones to continental red basins:an example from the Cretaceous strata in the Honggucheng and Xinsixiang regions of the Minhe Basin

There are gaps in basic units of sequence stratigraphy and sedimentation in both continental red basins and marine basins.The continental strata are always vertically persistent,but inextensive laterally.In this respect,the "strata-plate correlation" model should not be adaptable to continental strata.Caution should be exercised in the application of the fund-mental concepts and theories about sequence stratigraphy of marine strata to continental strata. A parasequence is a relatively conformable succession of genetically related beds or bedsets bounded by marine-flooding surfaces and their correlative surfaces.It represents several stages of initiation,culmination and waning of fluvial event deposition,and therefore may act as a basic element of a parasequence set.A parasequence set is a succession of genetically related parasequences which form a distinctive stacking pattern that is bounded,in many cases,by major marine-flooding surface and their correlative surfaces.Its tectonic settings and sedimentation always remain unchanged throughout an event cycle.The study of the Cretaceous strata in the Honggucheng and Xinsixiang regions of the Minhe Basin was conducted with the aid of parasequences,parasequence sets and lithologic zones,which may make it possible to study the horizontally separated strata in the division and correlation of regional strata in continental basins.