麻城-团风断裂带土氡特征及活动性研究

对麻城-团风断裂带的土氡（Rn）浓度进行测量，并与该区域地质剖面进行对比，探讨麻城-团风断裂带的位置、规模和产状等基本特征。结果表明，断裂带整体走向北北东，穿过阎家河镇和夫子河镇，大致倾向西，倾角较陡，破碎带宽度达数十m至100 m。基于实测土氡数据和现有的土氡断裂活动性评价方法认为，麻城-团风断裂带现今具有较强的活动性。断裂带土氡异常呈现出北强南弱的特征，推测其原因为：1）麻城-团风断裂带活动性自北向南有减弱的趋势；2）麻城6.0级地震增大了近震区氡气的逸散速率。

Study on Soid Radon Features and Activity Analysis of the Macheng-Tuanfeng Fault

The soil radon (Rn) concentration of the Macheng-Tuanfeng fault has been measured through radon measurement. A comparison of the measuring results and regional geological section leads to discussions of the geographical location, scale and occurrence of the Macheng-Tuanfeng fault. The result reveals that the major fault generally strikes NNE across the Fuzihe town and Yanjiahe town, dipping north and with a high dip angle, and the width of fracture zone ranges from tens of meters up to one hundred meters. Combined with the measured data and the available soil radon appraisal methods of fault activity, we consider that the Macheng-Tuanfeng fault still has a high level of activity. The data also indicates a soil radon anomaly with an imbalance between south and north; we supposed this for two reasons: 1) the activity of the Macheng-Tuanfeng fault presents a weakening tendency from north to south; 2) due to the Macheng magnitude 6.0 earthquake, the release rate of radon gas has increased near the earthquake area.