地震研究

利用2015年尼泊尔MW7.8地震发生前后喜马拉雅构造带中段地区境内外的GPS连续站及流动站资料,以优化后的BERNESE解算策略进行数据解算,通过同震位移场分析、典型基线的时间序列分析、速度场动态变化分析等多种手段分析地震发生前后的地壳形变特征。结果表明:该次地震并没有完全释放应力积累能量,震后印度板块推挤作用并未减缓,该区域构造应力积累仍处于较高水平,震情形势值得关注。

In this paper,we collect the GPS data in the middle section of the Himalayas structural belt before and after the 2015 25th April MW7.8 Gorkha,Nepal earthquake,including observation data from continuous and regional stations,and the data is solved using the BERNESE software.To study the crustal deformation before and after the Nepal earthquake,the coseismic displacement field,the typical baseline time series,and the velocity field analysis are carried out.The results show that the earthquake did not completely release the accumulated stress energy,and the push of the Indian plate did not slow down after the earthquake.Energy accumulation is still at a relatively high level,and we should pay more attention to the seismic risk.

引言
1 GPS同震位移场
2 基线时间序列
3 速度场变化
4 讨论和结论

图1 收集到的连续站及流动站数据站点分布<br/>Fig.1 Continuous and regional GPS stations distribution map

图1 收集到的连续站及流动站数据站点分布
Fig.1 Continuous and regional GPS stations distribution map

图2 GPS获得的尼泊尔MW7.8地震同震水平位移场<br/>Fig.2 Coseismic horizontal displacements caused by the 2015NepalMW7.8,earthquake,inferred from GPS observations

图2 GPS获得的尼泊尔MW7.8地震同震水平位移场
Fig.2 Coseismic horizontal displacements caused by the 2015NepalMW7.8,earthquake,inferred from GPS observations

图3 GPS获得的尼泊尔MW7.8地震同震垂直位移场<br/>Fig.3 Coseismic vertical displacements caused by the 2015 Nepal MW7.8,earthquake,inferred from GPS observations

图3 GPS获得的尼泊尔MW7.8地震同震垂直位移场
Fig.3 Coseismic vertical displacements caused by the 2015 Nepal MW7.8,earthquake,inferred from GPS observations

表1 GPS同震位移场结果<br/>Tab.1 Coseismic displacements of continuous GPS stations

表1 GPS同震位移场结果
Tab.1 Coseismic displacements of continuous GPS stations

图4 尼泊尔MW7.8地震前后跨喜马拉雅构造带GPS基线结果<br/>Fig.4 GPS baseline results across the Himalaya tectonic belt before and after the Nepal MW7.8 earthquake

图4 尼泊尔MW7.8地震前后跨喜马拉雅构造带GPS基线结果
Fig.4 GPS baseline results across the Himalaya tectonic belt before and after the Nepal MW7.8 earthquake

图5 跨喜马拉雅构造带与构造带两侧GPS基线结果对比<br/>Fig.5 Comparison of GPS baseline results of crossing the Himalaya tectonic belt and two sides of the tectonic belt

图5 跨喜马拉雅构造带与构造带两侧GPS基线结果对比
Fig.5 Comparison of GPS baseline results of crossing the Himalaya tectonic belt and two sides of the tectonic belt

图6 尼泊尔MW7.8地震前后两期速度场对比图(基于欧亚大陆基准)<br/>Fig.6 Two periods GPS velocity field before and after the 2015 Nepal MW7.8,earthquake(with respect to Eurasian plate)

图6 尼泊尔MW7.8地震前后两期速度场对比图(基于欧亚大陆基准)
Fig.6 Two periods GPS velocity field before and after the 2015 Nepal MW7.8,earthquake(with respect to Eurasian plate)

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备注

引言

1 GPS同震位移场

2 基线时间序列

3 速度场变化

4 讨论和结论

期刊信息