The China Seismo-Electromagnetic Satellite(CSES),China’s first satellite to measure geophysical fields with scientific goals in both space and solid earth physics,was launched successfully in February 2018.It carries...The China Seismo-Electromagnetic Satellite(CSES),China’s first satellite to measure geophysical fields with scientific goals in both space and solid earth physics,was launched successfully in February 2018.It carries high-precision magnetometers to measure the geomagnetic field.In this study,the CSES magnetic data were used to extract the signal of the lithospheric magnetic field caused by magnetized rocks in the crust and uppermost mantle.First,an along-track analysis of the CSES magnetic data was undertaken near the Bangui magnetic anomaly in central Africa and the Tarim magnetic anomaly in China,demonstrating that the CSES magnetic data are indeed sensitive to the lithospheric magnetic anomaly field.Then a lithospheric magnetic anomaly map over China and surrounding regions was derived.This map is consistent with the lithospheric part of the CHAOS-7 model.In particular,it clearly reveals four major magnetic anomalies containing long-wavelength signals at the altitude of lowearth-orbiting satellites.Three magnetic highs are located over the Tarim,Sichuan and Songliao basin,the origins of which could be related to large-scale tectonic-magmatic activities during geological history.A prominent magnetic low is otherwise found in the southern Himalayan-Tibetan plateau,possibly caused by the shallow Curie depth in this region.To further improve the precision of the lithospheric magnetic field model,more detailed data processing and multi-source data merging are needed.展开更多
By analyzing surface latent heat flux (SLHF) data from the NCEP/NCAR Reanalysis Project for the period three months before and after the Sept. 3, 2010 M S 7.1 New Zealand earthquake, an isolated SLHF positive anomaly ...By analyzing surface latent heat flux (SLHF) data from the NCEP/NCAR Reanalysis Project for the period three months before and after the Sept. 3, 2010 M S 7.1 New Zealand earthquake, an isolated SLHF positive anomaly on Aug. 1, 2010 was found with a high value of about 160 W/m 2 to the northeast of the epicenter. Historical data, background pixels, and wavelet transforms of time series were comprehensively analyzed to study the spatiotemporal features of the SLHF anomaly. After removing the influences of wind speed and cloud cover, the key factor leading to local SLHF anomalies is the surface temperature increment. Combined with GPS displacement observations and tectonic settings, we determined that the physical mechanism of the SLHF anomaly could possibly be attributed to hot underground materials related to high-temperature and high-pressure upwelling from the deep crust and mantle along the nearby subduction zone, thereby explaining the local temperature increment to the northeast of the epicenter, as well as in the center of the North Island and the southwest of the South Island. Furthermore, it changed the specific humidity between the ground and surface air, causing the local SLHF increment.展开更多
基金supported by the China Postdoctoral Science Foundation(Grant No.2019M660731)the National Key R&D(Research and Development)Program of China(Grant No.2018YFC1503500)+6 种基金ISSI-BJ(International Space Science Institute-Beijing)(Grant No.2019IT-33)supported as part of Swarm DISC activitiesfunded by ESA(Grant No.4000109587)supported by LIMADOU-Science Projectfunded by ASI(Italian Space Agency)supported by the Austrian Space Applications Programme(Grant No.873688)funded by the China National Space Administration(CNSA)China Earthquake Administration(CEA)。
文摘The China Seismo-Electromagnetic Satellite(CSES),China’s first satellite to measure geophysical fields with scientific goals in both space and solid earth physics,was launched successfully in February 2018.It carries high-precision magnetometers to measure the geomagnetic field.In this study,the CSES magnetic data were used to extract the signal of the lithospheric magnetic field caused by magnetized rocks in the crust and uppermost mantle.First,an along-track analysis of the CSES magnetic data was undertaken near the Bangui magnetic anomaly in central Africa and the Tarim magnetic anomaly in China,demonstrating that the CSES magnetic data are indeed sensitive to the lithospheric magnetic anomaly field.Then a lithospheric magnetic anomaly map over China and surrounding regions was derived.This map is consistent with the lithospheric part of the CHAOS-7 model.In particular,it clearly reveals four major magnetic anomalies containing long-wavelength signals at the altitude of lowearth-orbiting satellites.Three magnetic highs are located over the Tarim,Sichuan and Songliao basin,the origins of which could be related to large-scale tectonic-magmatic activities during geological history.A prominent magnetic low is otherwise found in the southern Himalayan-Tibetan plateau,possibly caused by the shallow Curie depth in this region.To further improve the precision of the lithospheric magnetic field model,more detailed data processing and multi-source data merging are needed.
基金supported by the National Basic Research Program of China (2011CB707102)the Fundamental Research Funds for the Central Universities (2010YD01)the Program of Scientific and Technological Cooperation Between Italy and China (SAGA-4-EPR)
文摘By analyzing surface latent heat flux (SLHF) data from the NCEP/NCAR Reanalysis Project for the period three months before and after the Sept. 3, 2010 M S 7.1 New Zealand earthquake, an isolated SLHF positive anomaly on Aug. 1, 2010 was found with a high value of about 160 W/m 2 to the northeast of the epicenter. Historical data, background pixels, and wavelet transforms of time series were comprehensively analyzed to study the spatiotemporal features of the SLHF anomaly. After removing the influences of wind speed and cloud cover, the key factor leading to local SLHF anomalies is the surface temperature increment. Combined with GPS displacement observations and tectonic settings, we determined that the physical mechanism of the SLHF anomaly could possibly be attributed to hot underground materials related to high-temperature and high-pressure upwelling from the deep crust and mantle along the nearby subduction zone, thereby explaining the local temperature increment to the northeast of the epicenter, as well as in the center of the North Island and the southwest of the South Island. Furthermore, it changed the specific humidity between the ground and surface air, causing the local SLHF increment.
