Fine-grained lacustrine sedimentary rocks are characterized by high continuity and resolution

and can faithfully record the changes in climate and environment of lacustrine basins.Considering the high stability during deposition

these sedimentary rocks have been regarded as good information carriers to identify Milankovitch cycles;while in return

the recognition of time connotation of the Milankovitch theory is an effective way to perform classification and correlation of high-frequency cycles

and to improve the temporal resolution of stratigraphic classification

thus being a powerful complement to the conventional sequence stratigraphy.The accurate identification of Milankovitch Cycles is the basis for the classification of high-frequency sequences in the fine-grained lacustrine sedimentary rocks

and constraining the variation of sedimentary rate is the key to the recognition of Milankovitch Cycles.In view of the fast transformation of sedimentary facies and strong heterogeneity in continental sedimentary sequences

we used the magnetic susceptibility as a proxy.In addition

the evolutive harmonic analysis (EHA) and average spectral misfit (ASM) techniques were introduced to constrain the vertical variation of sedimentary rate

so as to more accurately recognize signals of Milankovitch Cycles.Combined with the base level cycle theory in high-resolution sequence stratigraphy

we found that the fourth-order sequence corresponds to the medium-term base level cycle and the time is quantified as 405 ka;the fifth-order sequence corres-ponds to the short-term base level cycle and the time is quantified as 100 ka;and the sixth-order sequence corresponds to the super-short-term base level cycle ant the time is quantified as 40 ka.Finally

the periodic curves of long-eccentricity

short-eccentricity and tilt are taken as referential curves for classification of the fourth-

fifth-and sixth-order sequence

and thus the quantitative classification of high-frequency sequences of fine-grained lacustrine sedimentary rocks can be achieved.