Abstract：The major prospecting target in SWD area is Jurassic Sangonghe Group Second Segment (J1S2) that is characteristics of south-inclined single-slope configuration, simple structure and undeveloped faults,and the exploration objects are subtle strata traps. The major prospecting objective sand body is meandering river delta front branching channel sand body that is characteristics of good reservation of fine-grained contents on the top part of channels, smaller grain grade, relatively undeveloped sand (gravel) stones and rapid variation of lithology on plane,which easily forms typical sandstone pinch-out reservoir that is difficult to identify and describe this kind of traps. The dominant frequencies of seismic data in the area are 45-55Hz and identified minimum thickness of strata is about 25m,which can provide more reliable data foundation for subtle reservoir exploration in the area. Coming from seismic and geologic feature in the area, the paper created seismic and geologic interpretation mode through stratigraphic-sequence division of major targets, fine horizons labeling and seismic forward and inversion studies;effectively i-dentified and described subtle traps by using seis- mic attributes analysis techniques to study sedimentary facies and distribution regularity of sand bodies and combining with logging-constrained inversion technique, among which J1S21 lithologic traps in S4 block has been proved by latter drilling results
