断裂垂向封闭性演化定量研究方法及其应用

A Quantitative Study Method of Vertical Sealing Evolution of Fault and Its Application

在断裂垂向封闭机理及其评价方法研究的基础上,利用不同地质时期最大主应力方向与断裂走向之间夹角大小建立了一套断裂垂向封闭性演化的定量研究方法,并将其应用于乌尔逊凹陷北部5条主要断裂在大一段盖层内垂向封闭性演化的定量研究中,结果表明5条断裂在同一地质时期有着不同的垂向封闭性,而不同地质时期垂向封闭性的演化规律也是不同的。正是这一差异造成了它们在油气成藏与分布中的作用也就不同,F76号断裂垂向封闭性演化与南一段源岩排烃史匹配关系好,有利于油气聚集与保存,油气井分布最多;其次是F39和F21号断裂,有少量工业油气井分布;F80和F16号断裂最差,无工业油气井分布。这一结果表明该种方法用于断裂垂向封闭性演化的定量研究是可行的。

Based on the study of vertical sealing mechanism of fault and its evaluation method,a method studying quantitatively the evolution of vertical seal of fault is put forward by the angle between the oritentation of maximum principal compressive stress in different geological periods and the strike direction of fault is set up.The result indicates that five faults have different vertical sealing in the same geological period and evolution laws of their vertical sealing are different in different geological period.These differences causes the difference of them in oil-gas accumulation and distribution.The matching relationship between the evolution of vertical sealing of F76 fault and the hydrocarbon expulsion history is good,which is favorable for oil-gas to accumulate and preservation.There are the most industrial oil-gas wells to distribute along F76 fault.The second is F39 and F21 fault and there are a few industrial oil-gas wells to distribute along F39 and F21 fault.The worst are F80 and F16 faults,there are no industrial oil-gas wells to distribute along them.Field application indicates that the method is practical to study quantitatively the evolution of vertical sealing of fault.