GENETIC TYPES AND MECHANISMS OF THE CARBONATE ROCK METER-SCALE CYCLIC SEQUENCES

Four genetic types are sugggested for the carbonate rock meter-scale cyclic sequences on the basis of the previous study and field investigation made by the author. They are deep-water asymmetrical carbonate rock meter-scale cyclic sequences,limestone-marl meter-scale cyclic sequences,subtidal carbonate rock meter-scale sequences and tidal-flat carbonate rock meter-scale sequences. Their genetic mechanism is punctuated-aggradational allocyclic mechanism which is related to high-frequency cyclic sea-level changes resulted from the Milankovitch cycle. The criteria for recognition of these sequences include the types of the carbonate rocks, boundary nature and environments of the meter-scale cyclic sequences. The regularly vertical stacking patterns of the meter-scale cyclic sequences are interpreted as the basis for distinguishing third-order cyclic sequences.