为研究南昌新建—樵舍断裂土壤气体地球化学特征及构造地球化学背景，采用野外断层土壤气测量方法，于2021年4月和9月开展2期土壤气Rn、CO2的重复观测，结果发现：①土壤气浓度范围：第1期Rn、CO2的浓度范围分别为2 280—81 408 Bq/m3和0.09%—1.49%，背景值分别为21 984 Bq/m3和0.53 %；第2期Rn、CO2的浓度范围分别为5 560—97 000 Bq/m3和0.33%—7.05%，背景值分别为30 500 Bq/m3和1.44 %。②断裂带位置判定：测线上测点2附近土壤气浓度出现高值异常，由于气体在断裂带附近较为富集，判断此处可能为新建—樵舍断裂浅层位置所在。基于2期实测土壤气Rn浓度的断裂活动性评价结果，认为新建—樵舍断裂带现今活动较弱或活动不明显。本研究结果可为研究区土壤气的进一步研究和地质构造活动分析提供地球化学基础资料。
To study the geochemical characteristics of the soil gas and the tectono-geochemical background in Xinjian-Qiaoshe fault in Nanchang, the field fault soil gas measurement method was used to carry out two repeated observations of soil gas Rn and CO2 in April and September 2021. The results show that: ① Soil gas concentration range: The concentration of Rn and CO2 in the first phase ranges from 2 280 to 81408 Bq/m3 and 0.09% to 1.49%, respectively, with background values of 21 984 Bq/m3 and 0.53%. The concentration of Rn and CO2 in the second phase ranges from 5560 to 97 000 Bq/m3 and 0.33% to 7.05%, respectively, with background values of 30 500 Bq/m3 and 1.44%. ② Fault zone location determination: The concentration of soil gas near measuring point two on the measuring line is anomalous with high values. Since gas is relatively enriched near the fault zone, it is judged that this may be the shallow location of Xinjian-Qiaoshe fault. Based on the evaluation results of the fault activity of the soil gas Rn concentration measured in the two phases, it is considered that the Xinjiang-Qiaoshe fault zone is weak or not obvious at present. The results of this study can provide basic geochemical data for further study on soil gas and analysis of geological structure activities in the study area.
2023,44（6）: 70-77 收稿日期：2023-6-26
DOI：10.3969/j.issn.1003-3246.2023.06.011
基金项目：中国地震局监测、预报、科研三结合课题（项目编号：3JH-2021026）；江西省防震减灾与工程地质灾害探测工程研究中心、江西九江杨子块体东部地球动力学野外科学观测研究站开放基金（项目编号：OGYB202204）
作者简介：陈江贻（1988—），男，湖北监利人，硕士研究生，工程师，主要从事地震前兆流体和地震预报工作。E-mail：383152767@qq.com
参考文献：
车用太,刘耀炜,何鑭.断层带土壤气中H2观测——探索地震短临预报的新途径[J].地震,2015,35(4):1-10.
杜建国,宇文欣,李圣强,等.八宝山断裂带逸出氡的地球化学特征及其映震效能[J].地震,1998,18(2):155-162.
何超枫,陈州丰,齐信,等.麻城-团风断裂带土氡特征及活动性研究[J].大地测量与地球动力学,2016,36(6):504-507.
李源,马兴全,夏修军,等.河南新郑-太康断裂东段土壤气体地球化学特征[J].地震,2018,38(3):49-57.
李营,杜建国,王富宽,等.延怀盆地土壤气体地球化学特征[J].地震学报,2009,31(1):82-91.
缪阿丽,张扬,方震,等.郯庐断裂带新沂-泗洪段土壤气Rn体积活度和CO2浓度特征研究[J].地震,2019,39(1):48-57.
邵永新.土壤氡方法用于断层活动性研究的讨论[J].中国地震,2012,28(1):51-60.
孙小龙,王广才,邵志刚,等.海原断裂带土壤气与地下水地球化学特征研究[J].地学前缘,2016,23(3):140-150.
王博,黄辅琼,简春林.嘉峪关断层带土壤气氡的影响因素及映震效能分析[J].中国地震,2010,26(4):407-417.
周晓成,王传远,柴炽章,等.海原断裂带东南段土壤气体地球化学特征[J].地震地质,2011,33(1):123-132.
张平安.东莞某工程场地隐伏断裂a卡氡气勘测技术应用[J].西部探矿工程,2006,18(4):118-120.
张冠亚,周晓成,李营,等.怀安盆地北缘断裂东段土壤气体地球化学特征[J].地震,2015,35(3):113-122.
张慧,苏鹤军,李晨桦.合作市隐伏断层控制性地球化学探测场地试验[J].地震工程学报,2013,35(3):618-624.
张新基,张慧,苏鹤军,等.刘家堡活动断层土壤气氡、汞地球化学特征[J].地震,2005,25(4):87-92.
Giammanco S, Gurrieri S, Valenza M. Anomalous soil CO2 degassing in relation to faults and eruptive fissures on Mount Etna
(Sicily, Italy)[J]. Bulletin of Volcanology, 1998, 60(4):252-259.
King C Y, King B S, Evans W C, et al. Spatial radon anomalies on active faults in California[J]. Applied Geochemistry, 1996, 11(4):497-510.
Wakita H, Nakamura Y, Notsu K, et al. Radon anomaly:A possible precursor of the 1978 Izu-Oshima-Kinkai eauthquake[J]. Science, 1980, 207(4 433):882-883.
