汤西断裂带土壤气体地球化学特征与跨断层短水准变化的关系

为探究卫辉西代村跨断层短水准出现的趋势性变化与断裂活动间的相关性,在跨断层水准观测场地布设1条土壤气Rn和H2浓度测线,复测周期与跨断层水准测量周期基本一致,分别于2018年4月、7月、10月开展3期土壤气Rn和H2浓度测量.同时,为增加观测数据的可靠性,于2018年8月布设了1条与上述3期测线平行的测线并开展土壤气Rn和H2浓度测量.4期土壤气H2浓度测量结果显示,该区土壤气H2浓度背景值处于较低水平,H2浓度异常值所处位置主要集中在距起点150—210 m处,该处为断裂通过处.4期中Rn浓度最大值、背景值和均值的变化幅度均在正常范围内,Rn浓度异常值所处位置也主要集中在距起点150—210 m处,该处可能为断裂通过处.土壤气显示的断裂通过处与该区探槽显示的断裂位置一致.4期土壤气测量结果表明,近期汤西断裂带可能处于相对稳定状态,跨断层水准观测数据的趋势性变化与断裂活动之间相关性不大.

The relationship between geochemical character of soil gas and datachanges by short-leveling measurement across Tangxi fault

Soil gas concentration measurements can reveal the location and the activity characteristics of the fracture.The soil gas observation cross-fault was set in the short-leveling area,which is vertical to the direction of the fault,and it is used to find out whether there are any relationships between the trend anomaly of short-leveling and the fault activities in Xidai village.The measurement cycle of the soil gas is basically agree with the short-leveling and the hydrogen and the radon measurements were carried out in April,July and October 2018.Meanwhile,in order to guarantee the reliability of the data analysis,one term soil gas observation is added in August,2018.4 terms H 2 observation results show that the concentration is at low level and the anomalous section focus on about 150-210 m from its origin.The maximum,background and mean value of the Rn concentration from 4 terms change in the normal range and the anomalous section focus on about 120-270 m.The anomalous section of the cross-section dovetails with the surface exposure location of the fault zone speculated by the test trenches in this area.We can concluded fault is a stabilization period and the trend anomaly of short-leveling have little relationship to fault activity.