[关键词]
[摘要]
利用湖州地震台垂直摆倾斜仪、水管倾斜仪、伸缩仪和体应变仪等观测资料,采用功率谱密度估计方法,获得2011年3月11日日本9.0级大地震激发的0S5~0S50 基频球型自由振荡数据;比对PREM模型的理论计算周期,其相对偏差均小于1.2‰,且体应变观测的相对偏差最小;伸缩仪和体应变仪能清晰地检测到与地壳深部结构密切关系的0S2、0S3和0S4低阶振型。
[Key word]
[Abstract]
By using digital observations of the pendulum tilt-meter,water tube tilt-meter,extensometer and volume-strain-meter at Huzhou seismic station and with power spectrum density estimation method,we acquired 0S5~0S50 fundamental sphere free oscillations caused by the March 11,2011 Japan earthquake,and then compared it with PREM model. The relative errors are mostly smaller than 1.2‰. Extensometer and volume-strain-meter can clearly detect 0S2,0S3 and0S4 which is closely related to the deep structure and earth's interior.
[中图分类号]
[基金项目]
中国地震局三结合课题(CEA-JC/3JH-161101)、浙江省地震局科技项目(2015ZJJ03)联合资助