Guided by Vail's classical theory of sequence stratigraphy,the authors proposed to finely divide the Paleogene T Formation of the deepwater C Basin in South China Sea by tying wells in the shallow water area to the seismic sections in deepwater area.The results show that the proposed method works effectively in dealing with such problems as poor seismic data quality,lack of well data,complexities of faults,vague sequence boundaries caused by high temperature and high pressure,difficulties in stratigraphic tracing and correlation,and so on.By using the method,the authors also established fine three-dimensional isochronous stratigraphic sequence framework of the study area,divided the T Formation into four third-order sequences,and recognized seven kinds of sandbodies:braided deltas,fan deltas,incised valley,basin floor fan,turbidite fan,beach bar and shore sands.These sandbodies together with widely distributed mudstones of TST formed many lithologic-stratigraphic reservoirs in three kinds of accumulation mode:single fault,multiple fault,and slope.
