Abstract: Abstract:Self-organizing neural network (SONN) could be used to properly classify the studied objects according to the similarity of attributes from the objects, and avoid the shortcoming of back propagation neural network (BPNN) that learning samples have to be provided. The method by using SONN to auto-identify the seismic lithofacies from seismic data has been successfully applied in LGX oilfield of Tarim basin. From the lithofacies map, 6 faults controlled the hydrocarbon distribution in LGX oilfield, with extending in near east-west orientation, are revealed by using SONN method, which accord with the results from drilled wells. The study shows the feasibility of SONN in carbonate reservoirs.

Key words: Tarim basin, Lunnan area, carbonate reservoir, neural network, seismic data processing, seismic lithofacies