地震研究

2014年8月3日云南鲁甸发生M_S6.5地震,在震中及其周边地区分布的中国数字强震动台网的81个台站获取了这次地震的主震强震动记录。特别是位于极震区鲁甸龙头山镇财政所强震动台,完整记录到这次地震的地震动时程,其东西向PGA达948.5 cm/s²,该台站周边多栋多层建筑物底层完全倒塌和损毁,与记录所反映的强烈震动相吻合。初步分析强震动观测记录,讨论了本次地震的震中位置、破裂方向和强震动衰减速率等问题。

A M_S6.5 earthquake occurred in Ludian County of Yunnan Province on Aug. 3,2014. The strong motion caused by the mainshock was recorded by 81 strong motion observation stations which are located around the epicenter and its adjacent area. Especially,the strong motion station which is located at Longtoushan Office of Finance in the meizoseismal area perfectly recorded the strong ground motion time history of the mainshock,and the PGA of it is 948.5 cm·s^-2 in EW. The ground floors of many buildings around the Longtoushan strong motion stations damaged seriously or collapsed,which was consistent with the strong shock reflected in the recording. A preliminary analysis on the strong motion recordings were also done,based on these analysis,the problems about epicenter location,rupture direction and the attenuation of strong motion of Ludian M_S6.5 earthquake are also discussed.

引言
1 强震动观测台站及记录的强地面运动
2 强震动基本特征
3 分析与讨论
4 结语

图1 获取记录的强震动台站分布<br/>Fig.1 Distribution of strong motion stations of obtaining the main shock recording

图1 获取记录的强震动台站分布
Fig.1 Distribution of strong motion stations of obtaining the main shock recording

图2 部分台站东西向加速度时程<br/>Fig.2 Acceleration time histories in EW component recorded by some stations

图2 部分台站东西向加速度时程
Fig.2 Acceleration time histories in EW component recorded by some stations

表1 震中距≤50 km或PGA≥10 cm·s-2的强震动台站<br/>Tab.1 Strong motion stations that the epicenter distance≤50 km or PGA≥10 cm·s-2

表1 震中距≤50 km或PGA≥10 cm·s-2的强震动台站
Tab.1 Strong motion stations that the epicenter distance≤50 km or PGA≥10 cm·s-2

图3 鲁甸龙头山台站加速度时程<br/>Fig.3 Acceleration time history recorded by Longtoushan Strong Motion Station

图3 鲁甸龙头山台站加速度时程
Fig.3 Acceleration time history recorded by Longtoushan Strong Motion Station

图4 佳华广场38楼结构响应加速度时程<br/>Fig.4 Acceleration time history recorded by strong motion in the 38th floor of Jiahua Hotel

图4 佳华广场38楼结构响应加速度时程
Fig.4 Acceleration time history recorded by strong motion in the 38th floor of Jiahua Hotel

表2 PGA≥40 cm·s-2强震动台站场地条件<br/>Tab.2 Site Condition of Strong Motion Stations of PGA≥40 cm·s-2

表2 PGA≥40 cm·s-2强震动台站场地条件
Tab.2 Site Condition of Strong Motion Stations of PGA≥40 cm·s-2

图5 鲁甸地震实测PGA随震中距的变化<br/>Fig.5 PGA Attenuation of the Ludian main shock varied with distance

图5 鲁甸地震实测PGA随震中距的变化
Fig.5 PGA Attenuation of the Ludian main shock varied with distance

图6 龙头山强震动记录傅氏振幅谱<br/>Fig.6 Fourier amplitude spectrum of strong motion recording at Longtoushan Station

图6 龙头山强震动记录傅氏振幅谱
Fig.6 Fourier amplitude spectrum of strong motion recording at Longtoushan Station

图7 龙头山强震动记录加速度反应谱<br/>Fig.7 Acceleration response spectrum of strong motion recording at Longtoushan Station

图7 龙头山强震动记录加速度反应谱
Fig.7 Acceleration response spectrum of strong motion recording at Longtoushan Station

图8 龙头山强震动记录小波3层重构<br/>Fig.8 Third layer wavelet reconstruction of strong motion recording at Longtoushan Station

图8 龙头山强震动记录小波3层重构
Fig.8 Third layer wavelet reconstruction of strong motion recording at Longtoushan Station

图9 龙头山强震动记录小波6层重构<br/>Fig.9 Sixth layer wavelet reconstruction of strong motion recording at Longtoushan Station

图9 龙头山强震动记录小波6层重构
Fig.9 Sixth layer wavelet reconstruction of strong motion recording at Longtoushan Station

图10 鲁甸MS6.5地震记录PGA等值线图<br/>Fig.10 PGA isoline of Ludian MS6.5 main shock

图10 鲁甸MS6.5地震记录PGA等值线图
Fig.10 PGA isoline of Ludian MS6.5 main shock

图11 龙头山强震动记录地面运动位移轨迹<br/>Fig.11 Displacement orbit of the strong motion ground motion recording at Longtoushan Station

图11 龙头山强震动记录地面运动位移轨迹
Fig.11 Displacement orbit of the strong motion ground motion recording at Longtoushan Station

图12 龙头山强震动记录地面运动不同时刻的位移轨迹(图中时刻为相对时间)<br/>Fig.12 Displacement orbit of the ground motion at Longtoushan Station at different time (time is the relative time in the Figure)

图12 龙头山强震动记录地面运动不同时刻的位移轨迹(图中时刻为相对时间)
Fig.12 Displacement orbit of the ground motion at Longtoushan Station at different time (time is the relative time in the Figure)

图13 巧家铅厂强震动记录地面运动位移轨迹<br/>Fig 13 Displacement orbit of the ground motion at strong motion station located in Qianchang,Qiaojia County

图13 巧家铅厂强震动记录地面运动位移轨迹
Fig 13 Displacement orbit of the ground motion at strong motion station located in Qianchang,Qiaojia County

崔建文,高东,李世成,等.2006a.新的云南数字强震动观测台网[J].地震研究,29(增刊):453-458.
崔建文,李世成,高东,等.2006b.云南分区地震动衰减关系[J].地震研究,29(4):386-391.
非明伦,余庆坤,谢英情,等.2006.鲁甸5.6级地震震害分析[J].地震研究,29(1):87-91.
解丽,谢英情,非明伦,等.2008.2003年鲁甸5.1、5.0级地震震害异常影响因素分析[J].地震研究,31(增刊):607-611.
刘明才.2005.小波分析及其应用[M].北京:清华大学出版社出版.
阮祥,程万正.2008.云南鲁甸3次 MS≥5.0地震破裂参数的研究[J].地震学报,30(1):97-102.
闻学泽,杜方,易贵喜,等.2013.川滇交界东段昭通、莲峰断裂带的地震危险性背景[J].地球物理学报,56(10):3361-3367.
俞言祥,李山有,肖亮.2013.为新区划图编制所建立的地震动衰减关系[J].震灾防御技术,8(1):24-33.
周雍年.2006.中国大陆的强震动观测[J].国际地震动态,(11):1-6.
LI X.J.,ZHOU Z.H.,YU H.Y.,et al.2008.Strong Motion Observation and Recordings from Great Wenchuan Earthquake[J].Earthquake Engineering and Engineering Vibration,7(3):235-246.

备注

引言

1 强震动观测台站及记录的强地面运动

2 强震动基本特征

3 分析与讨论

4 结语

期刊信息