The key of high resolution isochronostratigraphic correlation is to identify multi-order stratigraphic cycles that represent multi-order base-level cycles in stratigraphic record.There bound to exist certain marks recording the time that corresponding order base-level cycle experienced in each stratigraphic cycle.The sedimentary and stratigraphic characteristics of stratigraphic cycles are: 1.vertical variation in single-phase physical properties; 2.variation in factes sequences and factes assemblage; 3.changes in cyclic stacking pattern; 4.stratigraphic geometry and contact relation.These characteristics reflect the variation of the ratio between containing space and sediment alimentation.Outcrop profile and well profile have higher resolution

and could be used to identify short term base-level cycles; well log could be used to identify mid-term base-level cycles; seismic profile could only by used to identify mid to long term base-level cycles due to the limitation of its resolution.The turnround point of base-level cycle would be selected as optimum position of high resolution isochronostratigraphic correlation.Time-space diagram is very effective on time-space inversion of stratigraphic profile and on checking the reliability of stratigraphic correlation.It has been proved by practice that the techniques could also be used in nonmarine strata.