Abstract: The geological conditions of block-B in Niger are complex, with characteristics of broken fault blocks, the intense fault activities, the complex fault relations, and the planar assemblage of fractures is of multiple solutions. How to accurately describe the fault system is the main problem to be solved at present.Based on the experiment and application of "two widths and one height" 3 D seismic data, the matching interpretation and evaluation techniques of "complex fault block trap identification and evaluation" and reservoir prediction techniques suitable for B block of Niger based on "two width and one height" data are formulated, which reduces the exploration risk and provides technical support for exploration and development of this block.