Abstract：Excellent result in identifying hydrocarbon seismic reflectionanomaly with the use of fuzzy mathematical method has been receivedin seismic exploration for non-anticlinal hydrocarbon reservoir intransitional zone between mid Sichuan and south Sichuan.The prin-ciple of the method is described systematically.It is also statedhow we choose index parameters by using specifically processed seis-mic data(pseudolog interval velocity,instantaneous amplitude en-velope section and instantaneous phase section)as well as seismic xe-flection time sections which underwent relative ampiitude preserva-Lion aiid high-resalution processings.The axticie presents some examples to show this method feasibie.Of 14 weds which penetrate the Maokou formation(fractured reser-voir)in the Yangxin series of Permian systems,10 wells,accountingfox 71.4x10-2 of the total wells,show excellent coincidence offuzzy cluster analysed gas production with real gas production;and 4welis,accounting for 28.6x10-2,manifest fairly good coincidence of thepredicted production with real production,In addition,prediction on theLeil reservoir(porous reservoir)of the Leikoupo formation of midTriassic system also brought satisfactory result.
