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Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing HAO Jin-Hui YANG Guang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and Liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

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Spatiotemporal evolution of wildfire activity during the PaleoceneEocene Thermal Maximum in China

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Science China Earth Sciences 2025年

作者： Xueting WANG Zuoling CHEN Linlin CUI Xu WANG State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Earth and Planetary Sciences Institute of geology and geophysics Chinese Academy of Sciences

The Paleocene-Eocene Thermal Maximum（PETM） was the most prominent warming event in the Cenozoic and serves as a geological analog for the current global warming driven by anthropogenic CO2emissions from burning fossil *** a primary disruptor of Earth's ecosystems, wildfire activity affects the balance of ecosystems, the global carbon cycle, and climate change. Therefore, studying the evolution and driving mechanisms of wildfires during the PETM is essential for predicting wildfire activity under global warming scenarios and for understanding the carbon cycle in the context of wildfire disturbances. Current research on wildfires during the PETM has mainly focused on the Northern Hemisphere, particularly Europe and North America, whereas studies on Chinese mainland remain limited. In this study, we analyzed black carbon（BC）concentration and carbon isotope(δ13C) in the Beigou section of the Nanyang Basin and the Xilutian section of the Fushun Basin to reconstruct the spatiotemporal evolution of wildfires in arid/semi-arid and humid zones. We integrated these findings with those of previous studies on the paleoclimate of the research area to elucidate the driving mechanisms behind wildfire occurrences. Our results indicate that wildfire activity weakened at the onset of the PETM, with the negative carbon isotope period characterized by low wildfire activity, except for a brief resurgence in the Nanyang Basin. During the recovery phase of the PETM, wildfire activity gradually increased, returning to the pre-PETM levels. The prolonged low wildfire state was likely caused by extremely high temperatures and precipitation as well as the resulting vegetation succession. During the PETM recovery phase, increased wildfire activity transformed “short-term carbon sinks” of the biological-atmospheric carbon cycle into “long-term carbon sinks” through the burial of BC. This process of carbon sink conversion may have acted as a negative feedback mechanism, contributing to carbo

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Solar cycles during the seventeenth century revealed by equatorial aurora records

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Earth and Planetary Physics 2025年第1期9卷 182-187页

作者： Yong Wei LiMei Yan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly

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Grounded-source short offset transient electromagnetic method:Theory and applications in deep mineral exploration

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Science China Earth Sciences 2025年

作者： Guoqiang XUE Xin WU Weiying CHEN Nannan ZHOU Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences

Abstract The Transient Electromagnetic (TEM) method is a critical geophysical technique for subsurface exploration of metal ore bodies, primarily utilizing either loop or grounded transmitters. The Long Offset Transient Electromagnetic(LOTEM) method employs a grounded-source transmitter, relying on a far-source observation mode and plane wave approximation for detection. However, LOTEM’s far-source configuration weakens signal strength, and the plane wave approximation reduces precision, limiting effective detection dept. to approximately 1000 m with a comprehensive error of about 15%. Recently, we have developed the grounded-source Short Offset Transient Electromagnetic (SOTEM) method,achieving greater detection dept. and accuracy within the 500–2000 m dept. range, a crucial interval for mineral resource exploration. This study explores the theoretical framework, instrumentation, data processing, and field applications of SOTEM. Based on a point charge element model, SOTEM accurately computes surface wave effects in EM field calculations,optimized for near-source observation. High-power, high-resolution, wide-bandwidth exploration equipment and an advanced three-dimensional hybrid inversion technique were also developed to enhance the method’s effectiveness. Application of SOTEM to the deep exploration of the Zhou’an Ni-Cu-PGE deposit in Henan Province yielded high-resolution imaging of conductivity structures to about 2.5 km dept.. These results, consistent with existing drill data, delineated mineralized ore bodies from surrounding formations, identified zones of mineralization potential, and suggested extensive resource prospects in the region.

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Coseismic surface ruptures of MW7.8 and MW7.5 earthquakes occurred on February 6, 2023, and seismic hazard assessment of the East Anatolian Fault Zone, Southeastern Türkiye

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Science China Earth Sciences 2025年

作者： Peng LIANG Yueren XU Xiaocheng ZHOU Ying LI Qinjian TIAN Huiping ZHANG Zhikun REN Jingxing YU Chuanyou LI Zheng GONG Shiguang WANG Aixia DOU Zifa MA Junjie LI Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake Administration China Earthquake Disaster Prevention Center State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration Institute of geophysics China Earthquake Administration

On February 6, 2023, southeastern Türkiye experienced a devastating earthquake doublet along the East Anatolian Fault（EAF）, with moment magnitude（MW） values of 7.8 and 7.5. These strong earthquakes resulted in at least 50,000 deaths and severe economic losses. Systematic research on coseismic surface ruptures induced by these events is vital for assessing the cascade rupture behaviors of plate boundary faults and future seismic hazards in the region. Interpretation of high-resolution post-earthquake satellite images and field investigations yielded the following results:（1） the two strong earthquakes had separate rupture zones. The first earthquake generated an approximately 280 km coseismic surface rupture along the southwestern segment of the main EAF, with 241 left-lateral displacements reaching up to 6.8±0.68 m, particularly 40 km northeast of the epicenter. The second earthquake produced a roughly 110 km surface rupture on an east-west branch of the EAF, with maximum displacements of 7.2±0.72 m.（2） The MW7.8 earthquake resulted in a cascading rupture across multiple segments of the southwestern section of the main EAF, with significantly variable displacements. The northeastern and southwestern parts of the main EAF and Malatya Fault remain at risk of strong earthquakes in the future.（3） The EAF rupture zone is densely populated, and due to the site amplification effect of loose sediments on foreland alluvial fans, foundation failures of buildings in the populated areas are common. Therefore, it is crucial to enhance the future seismic fortification capabilities in urban and rural areas along the EAF.

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An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan Qiu Department of geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

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Seismicity and Seismotectonics of Jeddah-Makkah Region, West-Central Saudi Arabia

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Journal of Earth Science 2015年第5期26卷 746-754页

作者： Mohammed Fnais Abdullah Al-Amri Kamal Abdelrahman Enayat Abdelmonem Sherif El-Hady geology & geophysics dept. College of Science King Saud University Seismology dept. National Research Institute of Astronomy and Geophysics geophysics dept. College of Earth Sciences King Abdul Aziz University

Jeddah-Makkah regionis have been suffering from earthquake crisis where some moderate to destructive earthquakes have been recorded. These earthquake activities are oriented along major faults or clustered in certain spots. Moreover, these earthquake events have annual recurrence periods, so the identification of these seismogenic source zones is of utmost importance for mapping the most hazardous localities which should be avoided in the future urban planning. Historical and instrumental earthquakes have been collected from national and international data centers and unified in catalogue. The existence of microearthquakes inland suggests that there is a significant level of tectonic activity at away from the axial trough of the Red Sea. Then, seismogenic source zones have been defined depending on the major tectonic trends; distribution of earthquake epicenters, seismicity rate（a ＆ b- values） and fault plane solution of major earthquakes. It is concluded that Jeddah-Makkah region is affected by the outlined five seismogenic source zones; three of these zones aligned of the main Red Sea axial trough（southwestern Jeddah, western Jeddah, and northwestern Jeddah zones）, while the other two zones are located in the land area of the region（Thewal-Rabegh and Jeddah-Makkah zones）. These inland zones correlated well with the main trends of major tectonics which refleet the reactivation of tectonic movements along these fault trends. The Red Sea zones are in agreement with the main path of the axial trough. The range of b-value in these identified zones is 0.65 to 1.03 through these identified zones. The area characterized by higher b-values could be indicative of a relative low stress regime which was a result of resulting from the stress release by the earthquakes. Whereas, the areas of lower b-values can be considered as an evidence of a relatively higher stress regime associated with a dominantly extensional stresses. Based on aforementioned, the region is suffering from

关键词： seismicity seismotectonic source zones b-value Jeddah

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Underground laboratories · Deep underground observation ·Scientific questions—Insights from observations of multi-physic fields in deep underground labs

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Science China Earth Sciences 2025年

作者： Huiqi REN Yun WANG Chang CHEN Guangyu FU Longqing QIU Lianghui GUO Chengliang XIE Yongsheng HE Heping SUN Jiwen TENG Institute of Defense Engineering Academy of Military Sciences State Kay Laboratory of Geological Processes and Mineral Resources Key Laboratory of Intraplate Volcanoes and Earthquakes Ministry of Education China University of Geosciences (Beijing) Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Institute of geology and geophysics Chinese Academy of Sciences

This paper presents a comprehensive review on recent development and research conducted in domestic and international underground laboratories. We first introduce the differences in three environments—surface, mountain tunnel cavities and underground coal mine tunnels—by examining cosmic ray background, ambient noises related to gravity and seismic measurement, and electromagnetic noises in magnetic and magnetotelluric measurements. We highlight potential misuse of the term Underground Lab or Deep Underground Lab when describing observations in different physical fields. We introduce unique features of underground coal mine tunnels in China, such as large spaces, ultra-quiet conditions, and ultra-clean environments. When comparing with mountain tunnel cavities and borehole observations, coal mine tunnel observations have superior long-term stability and high precision. Through observations and comparisons of multi-physic fields at surface and the deep underground, we find that the higher SNR seismic observations conducted in deep underground tunnels in coal mines are beneficial to improve velocity tomography of the solid earth. The gravity observation with a Superconducting Quantum Interference Device(SQUID) makes it possibly to capture slow earthquake, which has not been observed previously in the Chinese mainland. SQUID magnetic observations can detect fluctuations as weak as femto-Tesla(fT), enabling us to explore the attenuation of Schumann Resonance down to the solid Earth. This opens opportunities to investigate the connections between the Earth's magnetic field and the interactions within the human brain and heart. To improve the precision of quantum measurement,we should consider the possible effects of weak magnetic disturbances in deep underground environments. Finally, we discuss the importance of deep underground laboratories, observing facilities and techniques deployed in these laboratories, and their possible connection with respect to “deep space” an

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Postglacial sea-level changes and development stages of fluvial-estuarine system

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Acta Oceanologica Sinica 1993年第4期12卷 573-584页

作者： Li Congxian Department of Marine geology and geophysics, Tongji University, Shanghai 200092, China dept. of Marine geology & geophysics Tongji Univ. Shanghai 200092 China

-On the basis of the data obtained from the investigations on some rivers in China and Australia, the author discusses the spatial and temporal changes of various portions of fluvial-estuarine system during postglacial sea-level rising in present coastal and deltaic areas. The evolution of a fluvial-estuarine system can be divided into four development stages: early transgression, late transgression, stationary and regression. Early transgression brought about filling-in of the paleo-valley formed in low stand of sea level. In response to late transgression the estuaries were created, during the stationary stage the big swamp was developed. The regression led to estuaries to be filled with sediments and then became deltas. At the same locality the fluvial-estuarine system changed with time. In the transgressive period the lower reach of a river changed into an estuary, and then became nearshore area. In the regressive period the nearshore area changed into an estuary , and then became delta.

关键词： Sea-level fluvial-estuarine system postglacial period paleo-valley paleo-interfluve retrogressive aggrada-tion

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Mission and challenges of higher education: an interview with G.Q. Max Lu, the president of the University of Surrey

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National Science Review 2020年第6期7卷 1108-1113页

作者： Ling Wang Zhengtang Guo the Institute of geology and geophysics Chinese Academy of Sciences

The University of Surrey (referred to as Surrey hereafter) is one of the renowned universities in the UK that was established on 9 September1966 with the grant of its Royal Charter and its roots go back to Battersea Polytechnic Institute, founded in 1891. Surrey is the research hub of small satellites, mobile telecommunication and artificial intelligence in Europe. In 2016, Surrey was named as ‘Univer-

关键词： Biographies

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