Shan Xu, Chaojian Chen, Mikhail Kruglyakov, Alexey Kuvshinov, Rafael Rigaud, Xiangyun Hu
{"title":"在中国西南观察到的巨大翻车机:逼真的三维EM建模能重现它们吗?","authors":"Shan Xu, Chaojian Chen, Mikhail Kruglyakov, Alexey Kuvshinov, Rafael Rigaud, Xiangyun Hu","doi":"10.1186/s40623-023-01863-y","DOIUrl":null,"url":null,"abstract":"<p><strong>Abstract: </strong>Vertical magnetic transfer functions (tippers) estimated at a global/continental net of geomagnetic observatories/sites can be used to image the electrical conductivity structure of the Earth's crust and upper mantle (down to around 200 km). We estimated tippers at 54 geomagnetic observatories across China, aiming eventually to invert them in terms of subsurface three-dimensional (3-D) conductivity distribution. Strikingly, we obtained enormously large tippers at three inland observatories in southwest China. Large tippers are often observed at coastal/island observatories due to high conductivity contrasts between resistive bedrock and conductive seawater. However, tippers at those inland observatories appeared to be a few times larger than coastal/island tippers. As far as we know, such large tippers (reaching value 3) were never reported in any region worldwide. We perform electromagnetic simulations in 3-D conductivity models mimicking the geological setting and demonstrate that enormously large tippers are feasible and can be attributed to a current channeling effect.</p><p><strong>Graphical abstract: </strong></p>","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"75 1","pages":"109"},"PeriodicalIF":3.0000,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10348949/pdf/","citationCount":"0","resultStr":"{\"title\":\"Enormously large tippers observed in southwest China: can realistic 3-D EM modeling reproduce them?\",\"authors\":\"Shan Xu, Chaojian Chen, Mikhail Kruglyakov, Alexey Kuvshinov, Rafael Rigaud, Xiangyun Hu\",\"doi\":\"10.1186/s40623-023-01863-y\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Abstract: </strong>Vertical magnetic transfer functions (tippers) estimated at a global/continental net of geomagnetic observatories/sites can be used to image the electrical conductivity structure of the Earth's crust and upper mantle (down to around 200 km). We estimated tippers at 54 geomagnetic observatories across China, aiming eventually to invert them in terms of subsurface three-dimensional (3-D) conductivity distribution. Strikingly, we obtained enormously large tippers at three inland observatories in southwest China. Large tippers are often observed at coastal/island observatories due to high conductivity contrasts between resistive bedrock and conductive seawater. However, tippers at those inland observatories appeared to be a few times larger than coastal/island tippers. As far as we know, such large tippers (reaching value 3) were never reported in any region worldwide. We perform electromagnetic simulations in 3-D conductivity models mimicking the geological setting and demonstrate that enormously large tippers are feasible and can be attributed to a current channeling effect.</p><p><strong>Graphical abstract: </strong></p>\",\"PeriodicalId\":11409,\"journal\":{\"name\":\"Earth, Planets and Space\",\"volume\":\"75 1\",\"pages\":\"109\"},\"PeriodicalIF\":3.0000,\"publicationDate\":\"2023-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10348949/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Earth, Planets and Space\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.1186/s40623-023-01863-y\",\"RegionNum\":3,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2023/7/14 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Earth, Planets and Space","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1186/s40623-023-01863-y","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/7/14 0:00:00","PubModel":"Epub","JCR":"","JCRName":"","Score":null,"Total":0}
Enormously large tippers observed in southwest China: can realistic 3-D EM modeling reproduce them?
Abstract: Vertical magnetic transfer functions (tippers) estimated at a global/continental net of geomagnetic observatories/sites can be used to image the electrical conductivity structure of the Earth's crust and upper mantle (down to around 200 km). We estimated tippers at 54 geomagnetic observatories across China, aiming eventually to invert them in terms of subsurface three-dimensional (3-D) conductivity distribution. Strikingly, we obtained enormously large tippers at three inland observatories in southwest China. Large tippers are often observed at coastal/island observatories due to high conductivity contrasts between resistive bedrock and conductive seawater. However, tippers at those inland observatories appeared to be a few times larger than coastal/island tippers. As far as we know, such large tippers (reaching value 3) were never reported in any region worldwide. We perform electromagnetic simulations in 3-D conductivity models mimicking the geological setting and demonstrate that enormously large tippers are feasible and can be attributed to a current channeling effect.
期刊介绍:
Earth, Planets and Space (EPS) covers scientific articles in Earth and Planetary Sciences, particularly geomagnetism, aeronomy, space science, seismology, volcanology, geodesy, and planetary science. EPS also welcomes articles in new and interdisciplinary subjects, including instrumentations. Only new and original contents will be accepted for publication.