断裂破坏区域性泥岩盖层程度研究方法的改进

Improvement of research method on comprehensive damage degree of regional mudstone cap caused by faults

为了更加准确地研究断裂破坏区域性泥岩盖层程度,基于断裂破坏区域性泥岩盖层机理及程度的影响因素,通过断层岩和区域性泥岩盖层压实成岩程度代替其排替压力,改进了断裂破坏区域性泥岩盖层程度的研究方法,并将改进前后方法分别应用于研究海拉尔盆地贝尔凹陷呼和诺仁构造F1断裂破坏大一下段区域性泥岩盖层程度。结果表明:改进前后方法研究均得到测点9处F1断裂破坏大一下段区域性泥岩盖层程度最大,测点13处最小,其余测点介于二者之间,在测点1~8和12~15处有利于南一段源岩生成油气在大一下段区域性泥岩盖层之下南二段聚集与保存,但测点1~6无油气发现,是由于其构造位置低,油气供给不足,未充满所致,与目前F1断裂处南二段已发现油气分布相吻合。改进前方法研究成果虽与改进后方法研究成果具有相同的变化规律,但其值相对较大,低估了F1断裂破坏大一下段区域性泥岩盖层程度,表明改进后方法研究结果可能更符合地下实际,而且方便易行。

In order to study the degree of regional mudstone cap of fault failure more accurately,based on the factors affecting the mechanism and degree of regional mudstone cap of fault failure,the research method of regional mudstone cap of fault failure is improved by replacing its displacement pressure with the degree of compacting diagenesis of fault rock and regional mudstone cap.The improved method was applied to study the extent of regional mudstone cover in the lower first member of the Damoguaihe Formation(K1d1x)of F1 fault of Huhenuoren structure,Beier Sag,Hailaer Basin.The results show that both before and after the improvement of the method,it is found that the degree of regional mudstone cover in the K1d1x of F1 fracture at measuring point 9 is the largest,and that at measuring point 13 is the smallest,and the rest of the measuring points are between the two.The measuring points from 1 to 8 and from 12 to 15 are conducive to the accumulation and preservation of oil and gas generated in the source rock of the first member of the Nantun Formation(K1n1)and the second member of the Nantun Formation(K1n2)under the regional mudstone cover of the K1d1x,but no oil and gas is found at measuring point 1 to 6.It is due to the low structural position and insufficient oil and gas supply,which is consistent with the oil and gas distribution found in the K1n2 of the F1 fault.Although the research results of the improved method have the same variation rule as those of the improved method,their value is relatively large and underestimates the extent of the regional mudstone cover in the K1d1x of the F1 fracture failure,indicating that the research results of the improved method may be more consistent with the underground practice and convenient and feasible.