A method of detecting underground oil and gas resources: Principles, models and applications

Based on the basic principle of detecting underground oil and gas resources with the direct detector of the space source (CYT), the interpretation models of the strata lithology were established, and the characteristic of lithology detection curves of rocks were analyzed. According to the comprehensive energy value of strata lithology at different depths, the method of distinguishing the positions and properties of underground strata were discussed. The verification results of three examples showed that the detection coincidence rate of this method reached 78.5% and the correctness and effectiveness of the models were proved. Finally, the effect of stratigraphic dip on the detection error of underground oil and gas resources was analyzed in theory. The results showed that the detection error of this method was close to the range from 30% to 40% when the stratigraphic dip was 30°. Thus, it is the main reason for detection error that the average stratigraphic dip of detection sections of verification wells comes up to 26.3°.