Research toward understanding earthquakes at ultra-low frequencies by analyzing satellite altimetry data.

通过分析卫星测高数据来了解超低频地震的研究。

• 批准号: 06402016
• 负责人: OKUBO Shuhei
• 金额: $ 11.26万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06402016/
• 关键词: Geoid; Fault Motion; Altimetry; Satellite; Slow Earthquake; Silent Earthquake; Silent Earhquake

We have detected a significant subsidence of the sea level of the Pacific near the coast of Peru and Chile after the 1994 Bolivia earthquake by analyzing the TOPEX/POSEIDON satellite altimetry data. The isotropic pattern of the sea surface change indicates the existence of isotropic implosion source with time scale of less than 10 days. This finding provides the evidence for the phase change of mantle minerals as a critical factor for deep earthquakes.We presented a theory for displacement caused by a point dislocation in a radially heterogeneous spherical earth. The objective of this research was to constrain the fault model of the 1994 Bolivia earthquake by using GPS observations on the Pacific coast of the South American continent.In order to achieve well constrained fault model, we investigate the possibility of using absolute gravity values which complement the geoid height change. For that purpose, we verified the 1 microgal precision of the new generation absolute gravimeter FG5 by collocation with superconducting gravimeters.

通过分析1994年玻利维亚地震后TOPEX/POSEIDON卫星测高数据，我们发现了秘鲁和智利海岸附近太平洋海平面的明显下沉。海面变化的各向同性模式表明存在时间尺度小于10天的各向同性内爆源。这一发现为地幔矿物相变作为深地震的关键因素提供了证据。提出了径向非均质球形地球中点位错引起的位移理论。本研究的目的是利用南美大陆太平洋沿岸的GPS观测资料对1994年玻利维亚地震的断层模式进行约束。为了得到约束良好的断层模型，我们研究了利用重力绝对值来补充大地水准面高度变化的可能性。为此，我们通过与超导重力仪的配置，验证了新一代绝对重力仪FG5的1微加仑精度。

项目成果

Okubo,S(ed.R.Teisseyre): "Theory of Earthquake Premonitory and Fracture Processes" Polish Scientific Publishers PWN,Warsaw, 648 (1995)

Okubo,S（ed.R.Teissere）：“地震预兆和断裂过程理论”波兰科学出版社 PWN，华沙，648 (1995)

Okubo S.,S.Yoshida,T.Sato,Y.Tamura and Y.Imanishi: "Verilying precision of a new generation absolute gravimeter FG5-comparison with superconducting gravimeters and detection of oceanic loeanic tide" Geophys.Res.Lett. 24巻(印刷中). (1997)

Okubo S.、S. Yoshida、T. Sato、Y. Tamura 和 Y. Imanishi：“验证新一代绝对重力计 FG5 的精度 - 与超导重力计的比较以及海洋潮汐的检测” Geophys.Res.Lett。 24（正在出版）（1997）。

Sun W., P.Vanicek and S.Okubo: "Global displacements caused by point dislocations in a realistic earth model" J.Geophys. Res. 101, B4. 8561-8577 (1996)

Sun W.、P.Vanicek 和 S.Okubo：“现实地球模型中点位错引起的全局位移”J.Geophys。

大久保修平: "地震による重力変化" 月刊地球-重力・測地・ジオダイナミクス. 号外11. 144-148 (1995)

Shuhei Okubo：“地震引起的重力变化”月刊地球 - 重力、大地测量、地球动力学 Extra 11. 144-148 (1995)。

Sun W., and S.Okubo: "Spheroidal Displacement Due to Point Dislocations in a Spherical Earth (Part2) : Dislocation Love numbers" Chinese J.Geophys.38. 89-101 (1995)

孙W.和S.Okubo：“球形地球中点位错引起的球体位移（第二部分）：位错爱数”中文J.Geophys.38。