断层上断点埋深是隐伏活动断层地震危险性评价中的一个重要参数。在隐伏断层活动性研究中,钻孔探测是重要的探测手段之一(徐锡伟,2002),但由于标志地层发育的局限和钻探分辨能力的局限,识别的断层上断点埋深往往会大于实际埋深。为了减小这种误差,本文以银川隐伏生长断层探测钻孔联合地质剖面资料为基础,提出了一种生长指数法,用以推算隐伏生长断层的上断点埋深。得出的3个钻探场点的断层“理论上断点”埋深分别为:9.09m(新渠稍场点),7.86m(满春场点)和7.25m(板桥场点),小于钻探可识别的上断点埋深。经验证,这应更接近于断层的实际断错情况。
Buried depth of fault up-breakpoint is a important parameter in earthquake risk estimate of buried active fault. In study of the buried fault activity, drilling is one of the important exploration means, but as a result of localization of the marker horizon developed and drilling own resolving power, the depth of up-breakpoint which drilling can identify always deeper than the actual depth of fault up-breakpoint. In order to minish the error, based on the drill exploration composite geological section data in Yinchuan buried growth fault, put forward a sort of growth index means, to reckon depth of up-breakpoint of buried growth fault. From the account we gained the "academic up-breakpoint" depth of the 3 proving grounds in Yinchuan buried fault, the result is as follows: The academic up-breakpoint depth of Xingqushao proving grounds is 9.09m, in Manchun proving grounds, the academic up-breakpoint depth is 7.86m, in Banqiao proving grounds, the academic up-breakpoint depth is 7.25m. All of the results less than depth of the fault up-breakpoint that drilling can identify. By validate, much more close to actual broken complexion of the fault.