用浅层数字地震仪探测五台山山前活动断裂

Exploration of Active Fault in the Front of Wutaishan Mountain Using Shallow Digital Seismograph

一、引言重大工程的选址,如城市扩建、电厂、电站的选址,公路桥梁铺设,地热资源探查等等,都必须考虑场区及其周围断层的延伸、走向以及活动情况。近几年来,曾在北京的昌平,山西的繁峙、榆次、内蒙古的凉城、河北的石家庄、滦南县等地,为重点工程选址和寻找地热资源,利用MCSEIS-1600浅层数字地震仪,采取浅层反射、折射并用的方法探测断裂的延伸状况及活动性,均取得良好的效果,其中昌平、凉城经打井验证,探测结果与实际情况相吻合。本文介绍了利用MC-1600(48)道高分辩率浅层数字地震仪,在地形极其复杂的山西省繁峙县高里村与木角村之间进行的浅层人工地震勘探。通过对该区Ⅰ。

Selecting site of major project, such as extension of a city, power plant, bridge and geothermal prospecting and so on, we should take into consideration the fault, its spreading, strike, and activity in the structure site and around it. In recent years, we have sucessfully completed many major projects using shallow reflection and refraction seismics with Mcseis-1600 digital seismograph, for example, geothermal prospecting in Changping, Beijing. selecting site for major project in Fanshi and Yuci in Shanxi Province, Shijiazhuang and Luannan in Hebei Province and Liangcheng in Inner Mongolia and so on. This paper presents the shallow seismic prospecting result for the very complex situation of topography in Fanshi, Shanxi Province. It has given out geologic structure of three dimensional space, velocity profile, faults dispersing and occurrence with record of longitudinal and nonlongitudinal seismic prospecting line. The result has suggested that there are a large scale fault in metamorphic rock of the Archean Group with faulting distance of 85m (F_1), and two active rifts (F_2, F_3) of the Pliocene Epoch with faulting distance of 10m, respectively. All these faults form the fault system in the front of Wutaishan mountain and they control rising of fault block of the Wutaishan mountain and forming and developing of the Fan-Dai basin.