Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China
The geothermal zone of southeast China, which is one of the country’s known geothermal zones, contains significant natural geothermal resources. To understand the formation of geothermal resources, a magnetotelluric (MT) investigation with a site spacing of 1–2 km was carried out...
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2018-08-01
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author | Chaofeng Wu Xiangyun Hu Guiling Wang Yufei Xi Wenjing Lin Shuang Liu Bo Yang Jianchao Cai |
author_facet | Chaofeng Wu Xiangyun Hu Guiling Wang Yufei Xi Wenjing Lin Shuang Liu Bo Yang Jianchao Cai |
author_sort | Chaofeng Wu |
collection | DOAJ |
description | The geothermal zone of southeast China, which is one of the country’s known geothermal zones, contains significant natural geothermal resources. To understand the formation of geothermal resources, a magnetotelluric (MT) investigation with a site spacing of 1–2 km was carried out around the Zhangzhou Basin. The recorded MT data were processed by robust time series and remote reference processing techniques. The data analysis results revealed that two-dimensional (2-D) modeling can be used to approximately determine the electrical structure. The joint inversions of TE and TM modes have been performed after distortion decomposition. In the inversion models, a low resistivity cap of 200–800 m thickness was observed, which represented the blanketing sediments composed of Quaternary and volcanic rocks of the late Jurassic period. The presence of high resistivity above a depth of 20 km indicates the granites are widely developed in the upper and middle crust. MT measurements have revealed some deep-seated high conductive zones, which were inferred to be partially melting at depth of 8–17 km, which is likely to be reason behind the formation of higher-temperature hot springs. The results also show that there is a shallower Moho, which indicates that the heat from the upper mantle may have a big contribution to the surface heat flow. Fractures-controlled meteoric fluid circulation is the most likely explanation for the hot springs. |
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id | doaj.art-709bd2ee96b44bd4ade033aad2a3dbd2 |
institution | Directory Open Access Journal |
issn | 1996-1073 |
language | English |
last_indexed | 2024-04-11T20:41:42Z |
publishDate | 2018-08-01 |
publisher | MDPI AG |
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series | Energies |
spelling | doaj.art-709bd2ee96b44bd4ade033aad2a3dbd22022-12-22T04:04:12ZengMDPI AGEnergies1996-10732018-08-01118217010.3390/en11082170en11082170Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern ChinaChaofeng Wu0Xiangyun Hu1Guiling Wang2Yufei Xi3Wenjing Lin4Shuang Liu5Bo Yang6Jianchao Cai7Hubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaHubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaHubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaInstitute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang 050061, ChinaInstitute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang 050061, ChinaHubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaHubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaHubei Subsurface Multi-Scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, ChinaThe geothermal zone of southeast China, which is one of the country’s known geothermal zones, contains significant natural geothermal resources. To understand the formation of geothermal resources, a magnetotelluric (MT) investigation with a site spacing of 1–2 km was carried out around the Zhangzhou Basin. The recorded MT data were processed by robust time series and remote reference processing techniques. The data analysis results revealed that two-dimensional (2-D) modeling can be used to approximately determine the electrical structure. The joint inversions of TE and TM modes have been performed after distortion decomposition. In the inversion models, a low resistivity cap of 200–800 m thickness was observed, which represented the blanketing sediments composed of Quaternary and volcanic rocks of the late Jurassic period. The presence of high resistivity above a depth of 20 km indicates the granites are widely developed in the upper and middle crust. MT measurements have revealed some deep-seated high conductive zones, which were inferred to be partially melting at depth of 8–17 km, which is likely to be reason behind the formation of higher-temperature hot springs. The results also show that there is a shallower Moho, which indicates that the heat from the upper mantle may have a big contribution to the surface heat flow. Fractures-controlled meteoric fluid circulation is the most likely explanation for the hot springs.http://www.mdpi.com/1996-1073/11/8/2170magnetotelluricgeothermal anomalyhigh-conductive zoneZhangzhou Basin |
spellingShingle | Chaofeng Wu Xiangyun Hu Guiling Wang Yufei Xi Wenjing Lin Shuang Liu Bo Yang Jianchao Cai Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China Energies magnetotelluric geothermal anomaly high-conductive zone Zhangzhou Basin |
title | Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China |
title_full | Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China |
title_fullStr | Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China |
title_full_unstemmed | Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China |
title_short | Magnetotelluric Imaging of the Zhangzhou Basin Geothermal Zone, Southeastern China |
title_sort | magnetotelluric imaging of the zhangzhou basin geothermal zone southeastern china |
topic | magnetotelluric geothermal anomaly high-conductive zone Zhangzhou Basin |
url | http://www.mdpi.com/1996-1073/11/8/2170 |
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