A study on correction equations for the effect of seafloor topography on ocean bottom magnetotelluric data

被引:15
作者
Matsuno, Tetsuo [1 ]
Seama, Nobukazu
Baba, Kiyoshi
机构
[1] Kobe Univ, Grad Sch Sci & Technol, Kobe, Hyogo 6578501, Japan
[2] Kobe Univ, Res Ctr Inland Seas, Kobe, Hyogo 6578501, Japan
[3] Japan Agcy Marine Earth Sci & Technol, IFREE, Kanagawa 2370061, Japan
[4] Univ Tokyo, Earthquake Res Inst, Tokyo 1130032, Japan
来源
EARTH PLANETS AND SPACE | 2007年 / 59卷 / 08期
基金
日本学术振兴会;
关键词
marine magnetotellurics; seafloor topographic effect; correction of distortions;
D O I
10.1186/BF03352037
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
Consideration of the effect of seafloor topography on ocean bottom magnetotelluric data is needed to estimate a reliable resistivity structure. Selection of the correction equation which precisely takes account of distortions is important when we correct the effect of seafloor topography with forward modeling. Corrections of synthetic data based on three different correction equations are carried out, and the corrected responses and the true response are compared to investigate which correction equation is the best in application to distorted magnetotelluric data on the seafloor. Differences in the corrected responses are remarkable at periods shorter than several thousands seconds. These differences are caused by differences in treatment of the distortions of magnetic field and in robustness of the correction equation to a resistivity structure assumed for the topographic correction. The results suggest that the correction equation of Nolasco et al. (1998) should be used because it better accommodates the estimation of unknown resistivity structures. We apply the correction equation of Nolasco et al. (1998) to a response observed in the Mariana area. The one-dimensional resistivity structure estimated from the corrected response explains almost all the components of the observed response.
引用
收藏
页码:981 / 986
页数:6
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