地震研究

以GPS观测资料和部分地质方法所获得的断裂活动性参数为约束,基于弹性半无限空间断裂位错理论,反演获得庄浪河断裂、马衔山北缘断裂带各主要断裂段的现今滑动速率。结果表明,马衔山北缘断裂带的马衔山段左旋走滑较明显,量值达3.91 mm/a,而东、西两段走滑分量不明显,整个马衔山北缘断裂带有较明显的逆冲分量,以东段的内官营段逆冲倾滑最明显,量值达3.0 mm/a; 庄浪河断裂有0.5～1.2 mm/a的逆倾滑分量,走滑分量不明显。在此基础上,计算了各个断裂段的地震复发间隔,并运用时间相依的概率模型计算了未来30 a、50 a和100 a的发震概率。

Constrained by the fault active parameter which is obtained by the GPS observations data and the geology method,based on elastic semi-infinite space fault dislocation theory,we obtained the current sliding rates of the main segments of the Zhuanglanghe Fault and Maxianshan North Edge Fault by inversion method. The result suggests that the left-lateral strike-slip of Maxianshan segment of the Maxianshan North Edge Fault is obvious and its rate is 3.91 mm/a,while the strike-slip of eastern and western segments is not obvious. The whole Maxianshan North Edge Fault has the obvious thrust component,and the thrusting dip-slip of eastern segment is the most obvious and the rate reach to 3.0 mm/a. The Zhuanglanghe Fault has the reverse dip-slip component of 0.5～1.2 mm/a,and the strike-slip component is not obvious. On the basis of it,we calculate the earthquake recurrence interval for each fault segment,and the probability of earthquake occurrence in the next 30,50 and 100 years by use of time-dependent probabilistic model.

引言
1 活动断裂的滑动速率反演 1.1 深大断裂位错模型
2 复发间隔估算
3 发震概率计算
4 结论与讨论

图1 深断裂位错模型示意图<br/>(a)深部活动断裂与地表形变场的关系模型; <br/>(b)有限矩形断层面<br/>Fig.1 Schematic diagram of “Three-dimensional Deep-fault Dislocation Model”(a)Relationship model between deep active faults and surface deformation field;(b)finite rectangular

图1 深断裂位错模型示意图
(a)深部活动断裂与地表形变场的关系模型;
(b)有限矩形断层面
Fig.1 Schematic diagram of “Three-dimensional Deep-fault Dislocation Model”(a)Relationship model between deep active faults and surface deformation field;(b)finite rectangular

图2 庄浪河断裂带、马衔山北缘断裂带及附近GPS站点分布<br/>Fig.2 Distribution of the selected GPS stations cross Zhuanglanghe Fault and Maxianshan North Edge Fault

图2 庄浪河断裂带、马衔山北缘断裂带及附近GPS站点分布
Fig.2 Distribution of the selected GPS stations cross Zhuanglanghe Fault and Maxianshan North Edge Fault

表1 庄浪河断裂及马衔山北缘断裂带各段划分情况<br/>Tab.1 Classification of each segment of the Zhuanglanghe Faults and the Maxianshan North Edge Fault

表1 庄浪河断裂及马衔山北缘断裂带各段划分情况
Tab.1 Classification of each segment of the Zhuanglanghe Faults and the Maxianshan North Edge Fault

图3 庄浪河断裂及马衔山北缘断裂带邻近区域<br/>的GPS站点观测速度与反演速度对比图<br/>Fig.3 Comparision of observation and inversion velocity field of GPS sites cross the Zhuanglanghe Fault and Maxianshan North Edge Fault

图3 庄浪河断裂及马衔山北缘断裂带邻近区域
的GPS站点观测速度与反演速度对比图
Fig.3 Comparision of observation and inversion velocity field of GPS sites cross the Zhuanglanghe Fault and Maxianshan North Edge Fault

表2 基于GPS数据反演得到的庄浪河断裂及马衔山北缘断裂带各断裂段现今滑动速率<br/>Tab.2 Sliding velocity of each segment of Zhuanglanghe Fault and Maxianshan North Edge Fault inversed based on GPS data

表2 基于GPS数据反演得到的庄浪河断裂及马衔山北缘断裂带各断裂段现今滑动速率
Tab.2 Sliding velocity of each segment of Zhuanglanghe Fault and Maxianshan North Edge Fault inversed based on GPS data

表3 马衔山北缘断裂及庄浪河断裂地震复发间隔和条件概率<br/>Tab.3 Earthquake recurrence interval and condition probability of the Maxianshan North Edge Fault and the Zhuanglanghe Fault

表3 马衔山北缘断裂及庄浪河断裂地震复发间隔和条件概率
Tab.3 Earthquake recurrence interval and condition probability of the Maxianshan North Edge Fault and the Zhuanglanghe Fault

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备注

引言

1 活动断裂的滑动速率反演 1.1 深大断裂位错模型

2 复发间隔估算

3 发震概率计算

4 结论与讨论

期刊信息