Abstract: Base-level circles and high-frequency sequences for the formations of well tc2 were identified in the light of stratigraphic base-level principle proposed by t. A. Cross. The middle circle fits the sequence, which is indicated by a whole baselevel rising and downward circle, and only the fluvial sequences
(s11, s12, s13) lack downward circle deposition; the rising circle includes lowstand and water progradation system; the downward circle belongs to high-stand. The results are significant for accurate correlation of sand layers and prediction of reservoirs in the studied area. The three types of parasequence were distinguished in this paper, which are different from the
concept of classic sequence stratigraphy.

Key words: stratigraphic base level, parasequence set, sequence, sandbed correlation, Turpan-Hami basin