摘要
采用地气测量方法,探测二郎山隧道隧址区内的隐伏断裂。通过处理和对比分析该地区内5条典型剖面的测量数据,有效判定断裂是否存在及其在地表的出露位置、规模等部分几何特征,并分析了隐伏断层地气元素的异常特征。结果显示:二郎山隧道隧址区推测断层的测线上存在地气异常,且其显示出良好的异常与构造的对应性;与成岩关系较密切的La、Ce、Nd、Sm、Y、Cd、Cu、Zn、Sr、Pb等元素灵敏度高、峰值明显,均能较好地反应隐伏断裂的存在;地气异常的高低与断层切割深浅和断层活动性存在一定的联系。
The method of geogas measurement was used to detect concealed fault at the site of Erlangshan tunnel.Through processing and comparative analysis of data of five typical sections,the paper determined effectively the existence,the position of outcrops,the dimension and geometrical features of fault,and analyzed the abnormal characteristics of geogas elements of concealed fault.The results show that there exists geogas anomaly along the survey line above the inferred fault at the site of Erlangshan tunnel,and the anomaly has good correspondency to structure.Elements closely related to diagenesis such as La,Ce,Nd,Sm,y,Cd,Cu,Sr,Pb have high sensibility and evident peak,can well reflect the existence of concealed fault.There exists certain relation between the amplitude of geogas anomaly,the cutting depth of fault and the activity of fault.
引文
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