中国地震局地壳形变观测台网布设有垂直摆倾斜仪、钻孔倾斜仪、洞体应变仪、分量式钻孔应变仪与体应变仪等地形变观测仪器。这些观测仪器均记录到了2011年日本M_W9.0大地震激发的自由振荡信号。本文分别利用单台数据和多台数据叠积，检测到₀S₃～₀S₃₀全部的球型自由振荡基频振型和₀T₃～₀T₂₀全部的环型自由振荡基频振型及部分谐频振型。此外，通过对这些检测结果的对比，分析了它们对不同自由振荡类型、不同频段的振型检测能力。分析发现垂直摆倾斜仪对球型自由振荡的检测结果最佳，且由于在低频段有较高的噪声干扰，钻孔倾斜仪无法检测到低阶的球型自由振荡。对于环型自由振荡的检测，分量式钻孔应变仪检测结果最佳。

The Crustal Deformation Observatory Network of China Earthquake Administration equips with many kinds of crustal deformation observation instruments. These instruments have recorded the earth's free oscillation excited by the Japan M_W9.0 earthquake. All of the spheroidal oscillation modes(₀S₃~₀S₃₀)and toroidal oscillation modes(₀T₃~₀T₂₀)excited by the Japan M_W9.0 earthquake were detected through processing and analyzing those single or multiple group observation data. In addition,through comparing the different detective results obtained by those instruments,we analyze their capacity to observe different kinds of oscillation and different frequency band modes. We find that,the vertical pendulum tiltmeter has the best result for observing spheroidal oscillation. Because of the high noise in low frequency band,the borehole tiltmeter cannot observe the low-order spheroidal oscillation. The multi-component borehole strainmeter has a best result for observing toroidal oscillation,and the tunnel extension meters can only observe some low-order modes.

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中国地震局科研专项（17A18ZX085）资助