气候变化领域集成服务门户(CCPortal): Modeling Geoelectric Fields Induced by Geomagnetic Disturbances in 3D Subsurface Geology, an Example From Southeastern Australia

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DOI	10.1029/2020JB019843
	Modeling Geoelectric Fields Induced by Geomagnetic Disturbances in 3D Subsurface Geology, an Example From Southeastern Australia
	Wang L.; Duan J.; Hitchman A.P.; Lewis A.M.; Jones W.V.
发表日期	2020
ISSN	21699313
卷号	125 期号:9
英文摘要	Geomagnetic storms can cause power grid instabilities and blackouts due to excessive geomagnetically induced currents (GICs) flowing in electric transmission systems. In this study, we assess regional vulnerability to GICs by modeling the geoelectric fields induced by significant historic geomagnetic disturbance events in the presence of 3D subsurface geology using data from the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) magnetotelluric array, Australia-Wide Array of Geomagnetic Stations (AWAGS) magnetometer array, and Geoscience Australia geomagnetic observatory network. We analyze the vertical component of the magnetic field with respect to the horizontal magnetic-field polarization for two magnetic storms and gain insight into the inductive effects associated with field polarization orientations in the 3D case. We also analyze the telluric field intensity and polarization for a unit geomagnetic field polarized in northerly and easterly directions at AusLAMP sites and find that in the presence of 3D geology the induced field has a very polarization-sensitive anomaly. We model the geoelectric fields in southeastern Australia for the 1989 “Québec storm.” The induced ground electric fields are typically in the range 1,000–2,000 mV/km with a few sites within 2,000–5,000 mV/km on highly resistive regions and in coastal areas, and below 300 mV/km on inland sedimentary basins. The current study focuses on magnetic-field variations with periods between 120 and ~20,000 s due to bandwidth limits in our magnetotelluric tensor data and the Nyquist limit for the 60 s sampling of our geomagnetic-field data. Hence, our modeled maximum values should be considered lower estimates of potential real values. ©2020 Geoscience Australia, Commonwealth of Australia
英文关键词	3D conductivity structures; geomagnetic hazard; geomagnetically induced fields
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187636
作者单位	Geoscience Australia, Canberra, Australia
推荐引用方式 GB/T 7714	Wang L.,Duan J.,Hitchman A.P.,et al. Modeling Geoelectric Fields Induced by Geomagnetic Disturbances in 3D Subsurface Geology, an Example From Southeastern Australia[J],2020,125(9).
APA	Wang L.,Duan J.,Hitchman A.P.,Lewis A.M.,&Jones W.V..(2020).Modeling Geoelectric Fields Induced by Geomagnetic Disturbances in 3D Subsurface Geology, an Example From Southeastern Australia.Journal of Geophysical Research: Solid Earth,125(9).
MLA	Wang L.,et al."Modeling Geoelectric Fields Induced by Geomagnetic Disturbances in 3D Subsurface Geology, an Example From Southeastern Australia".Journal of Geophysical Research: Solid Earth 125.9(2020).