APPLICATION OF SEISMIC STRATIGRAPHY TO YANGJIANG DEPRESSION

In this paper, seismic stratigraphy is applied to interpret the sequences, structural characteristics and depositional facies in Yangjiang District, and the oil/gas prospects are evaluated as well. Ⅰ. Based on the seismic stratigraphic analysis, the Meso-Cenozoic sequences in the depression can be divided by two erosional hiatus, two truncations, three onlaps and a toplap unconformity. Ⅱ. According to the configurations and patterns of the seismic reflections, it is revealed that some growth normal faults developed in the depression. with rolling anticlines and antithetic normal faults during Meso-Cenozoic times there Then, the depression was transformed into a "V" shaped extensional basin by the successive tractions. Ⅲ. Nine types of seismic facies units are classified and the depositional facies belt are established based on the integrated analysis of seismic reflection configurations, structures, and reflective amplitudes combined with other informations. Ⅳ. According to the distribution of strong phase amplitude anomalies ("facies surface"), the possible oil-gas prospects are predicted without the analysis of seismic velocity and frequency.