地质构造复杂地区山前隐伏断裂的地震反射和折射联合探测

Joint application of reflection and refraction seismic exploration approach to piedmont buried fault at complex geotectonic conditions

采用地震反射和折射联合探测方法在襄樊-广济断裂带蕲州段上获得了高精度的反射时间剖面和折射速度剖面图像,这些图像清晰地显示了剖面浅部地层的分层特征和地层的速度变化特征.解释获得了襄樊-广济断裂带主断裂的位置、性质,初步判断了其活动性特征,确定了该断裂不是一条简单的断裂,而是一条由多条断裂组成的断裂带.这不仅在方法上具有一定普遍意义,而且为评价测区工程和民用建筑物所在区域的断裂活动性提供了可靠的基础资料.

Seismic reflection and refraction exploration techniques have its advantages and limitations to exploring the piedmont buried fault in front of mountain at that complex segment in geotectonic aspect.So ajoint of reflection and refraction seismic exploration approach is applied for this case and make best use of the advantages and bypass the disadvantages to infer the location,nature and preliminary activity of the faults.Here,seismic reflection and refraction are jointed to detect the Qizhou segment of the XiangfanGuangji fault belt and yield a high-precision time profile of reflection and velocity profile of refraction.These results illustrate a sequence in the shallow and a variation velocity of whole strata.Therefore,the main rupture location,fault property and activity were characterized to be a fault belt rather than a single fault.So it’s believed that this joint exploration is not only a universal significance in methodology but alsoan important data for the evaluation of the fault activity surrounding the civil engineering.