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对四川南部35口正钻井采用多种地震信息综合预报油气的成功率可达70％以上,而仅使用单一信息预报的成功率只有40—55％左右。在应用多种地震信息时,不是简单地从定性的角度去推断油气的存在,而是借用数理统计学中的“置信度”概念去度量,也就是说研究这些统计信息出现的概率。根据各信息因子对油气控制作用的大小,依据 Bayes 定理给出各个信息因子检测油气的权限分配公式。文中选用了六种预测才法,并从回报率及信息比的角度评价了这些方法的优劣,认为 Bayes—L 法最好。就同一方法而言,信息因子的个数不同,其预测的结果也不同。经验表明,阳新统顶部的视极性及振幅比(KZ~6)、瞬时相位(φ)和阳新统顶的构造曲率(ρ)是预测气况的决定因素。
The success rate of comprehensive prediction of oil and gas by using a variety of seismic information for 35 wells drilled in the south of Sichuan Province can reach over 70%, while the success rate of using only single information prediction is only 40-55%. When applying a variety of seismic information, instead of simply inferring the existence of oil and gas from a qualitative point of view, we use the concept of “confidence” in mathematical statistics to measure, that is to say, the probability of occurrence of these statistics. According to the effect of each information factor on the control of oil and gas, according to the Bayes theorem, the distribution formula of the right of each information factor to detect oil and gas is given. In this paper, six kinds of forecasting methods are selected, and the advantages and disadvantages of these methods are evaluated from the perspective of the rate of return and the information ratio, and the Bayes-L method is the best. In terms of the same method, the number of information factors is different and their forecasting results are also different. Experience has shown that the apparent polarities and amplitude ratios (KZ ~ 6), instantaneous phase (φ) and the tectonic curvature (ρ) of the Yangocene top are the decisive factors in predicting the gas status.