Abstract:

Sedimentary facies planar distribution of the Permian Changxing Formation, in Jiannan area, has been a considerable controversy,  which seriously restricted prediction of reef and beach development zone.  In the actual research, based on carbonate sedimentary theory,using the research ideas and methods of seismic sedimentology, by  single well data information, reflection characteristics of seismic facies are analyzed in the perspective of geological significance, seismic recognition modes of sedimentary facies are established, and sedimentary facies distribution and evolution are analyzed by palaeogeomorphology reconstruction and attribute analysis. The results show that: By combining well and seismic, conducted calibration sequence of reef, the features of seismic phase can well reflect the reef and bank development periods. Combined seismic profile with planar  facies identification, in the middle of the research area mainly developed continental shelf,which were with low frequency and low amplitude reflection that can be explained that the Kaijiang-Liangping shelf has extended to the study area. The seismic multiple attributes analysis can describe actual boundary of sedimentary facies and reef distribution range. Isochronous stratigraphic sections reflect that the late three-order SQ1 period is mainly reefs development period. In the SQ2 period, sea level became shallow and development site of exposed shoal areas migrated.

Key words: seismic sedimentology, Changxing Formation, organic reef, geological interpretation, ancient landform