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Editorial note for the Geodesy and Geodynamics journal special issue:Remote Sensing and GIS applications in crustal deformation and neotectonics

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Geodesy and Geodynamics 2022年第3期13卷 189-191页

作者： Ajay Kumar Taloor Girish Chandra Kothyari Shangmin Zhao Rajwant Mayank Joshi Department of Remote Sensing and GIS University of JammuJammu 180006India Active Fault Research Group Institute of Seismological ResearchGandhinagar 382009India Department of Surveying and Mapping Taiyuan University of Technology No.79Yingze West RoadTaiyuan 030024China Science and Engineering Research Board Government of IndiaNew Delhi 110016India GB Pant Institute of Himalayan Environment Sikkim Regional Centre Pangthang 737101India

crustal deformation and neotectonics are well-understood phenomena that happen almost on every part of the Earth and have some diastrophic effects on the Earth’s *** understand these effects,Remote Sensing(RS)and(GIS)have sharpened the human ability to learn about the scientiflc reasons for the Earth’s dynamic activities,including active tectonics and surface landform changes in spatially and temporally.

关键词： tectonics Earth crustal

Zircon U-Pb age evidence of the Mesoarchean(2.9–3.2 Ga)crustal remnant in the Southern Dabie Orogen,South China

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China Geology 2023年第1期6卷 174-176页

作者： Da-liang Xu Lian-hong Peng Xin Deng Chao-ran Liu Le Wan Xiao-ming Zhao Research Center for Petrogenesis and Mineralization of Granitoid Rocks China Geological SurveyWuhan 430205China Wuhan Center of China Geological Survey(China Central South China Innovation Center for Geosciences) Ministry of Natural ResourcesWuhan 430205China China University of Geosciences Beijing 100083China School of Earth Science China University of GeoscienceWuhan 430074China Institute of Karst Geology CAGSGuilin 541004China

*** Unlike the North China Plate where Archean and Paleoproterozoic crustal rocks are widely distributed,Early Precambrian basement rocks in the Yangtze Block of South China are locally exposed(Fig.1a),such as in the Kongling Complex,the Zhongxiang Complex,and the Douling Complex(Zhao GC and Cawood PA,2012).The Dabie Orogen is the eastward extension of the Qinling Orogen.

关键词： crustal Dabie South

crustal structure study based on principal component analysis of receiver functions

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Science China Earth Sciences 2019年第7期62卷 1110-1124页

作者： Jianyong ZHANG Ling CHEN Xu WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences

The receiver function(RF) technique is an effective method for studying crustal structure. For a single station, the average 1-D crustal structure is usually derived by stacking the radial RFs from all back-azimuths, whereas structural variations(such as dipping discontinuities or anisotropy) can be constrained through analysis of waveform dependence on the backazimuth of both the radial and tangential RFs. However, it is often difficult to directly extract information about structural variations from the waveform of RF, due to the common presence of noise in real data. In this study, we proposed a new method to derive structural variation information for individual stations by applying principal component analysis(PCA) to RFs sorted by back-azimuth. In this method(termed as RF-PCA), a set of principal components(PCs), which are uncorrelated with each other and reflect different characteristics of the RF data, were extracted and utilized separately to reconstruct new RFs. Synthetic tests show that the first PC of the radial RFs contains the average structural information of the crust beneath the corresponding station, and the second PC of the radial RFs and the first PC of the tangential RFs both reflect the variations of the crustal structure. Our synthetic modeling results indicate that the new RF-PCA method is valid for a variety of synthetic models with intra-crustal dipping discontinuities and/or anisotropy. We applied this method to the real data from a broadband temporary seismic station(s233) in the central part of the Sichuan Basin. The results suggest that the RF data can be best explained by the presence of two nearly parallel dipping discontinuities within the crust. Combining with previous logging data, seismic exploration and deep sounding observations, we interpret the shallow dipping discontinuity as the top boundary of the Precambrian crystalline basement of the Sichuan Basin and the deep one corresponding to the Conrad interface between the upper a

关键词： Principal component analysis Receiver function crustal structure Dipping discontinuity Anisotropy Sichuan Basin

crustal reworking and orogenic styles inferred from zircon Hf isotopes:Proterozoic examples from the North Atlantic region

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Geoscience Frontiers 2019年第2期10卷 417-424页

作者： C.J.Spencer C.L.Kirkland A.R.Prave R.A.Strachan V.Pease Earth Dynamics Research Group The Institute of Geoscience Research (TIGeR)Department of Applied GeologyCurtin University Centre for Exploration Targeting d Curtin Node Department of Applied GeologyCurtin University Department of Earth and Environmental Sciences University of St Andrews School of Earth and Environmental Sciences University of Portsmouth Department of Geological Sciences Stockholm University

Zircon Hf evolutionary patterns are powerful tools to investiage magma petrogenesis and crustal evolution. The ^(176)Hf/^(177)Hf isotopic signature of a rock is particularly informative and can be used to derive an estimation of the time when mantle extraction and diagnose closed system reworking where successive samples through time define an Hf evolution array dependant on the source Lu/Hf ratio. However, many magmatic events require new mantle addition as the thermal impetus for melting pre-existing crust. In this situation, rather than simply reflecting reworking, the isotopic signature indicates mixing with contributions from both reworked crust and new radiogenic input. Different geodynamic settings have different propensities for either reworking or addition of new mantle-derived magma. Hence, Hf-time trends carry within them a record, albeit cryptic, of the evolving geodynamic environment as different tectonic configurations recycle and add new crust at different rates, magnitudes, and from different sources. As an example of the difference in apparent Hf evolution slopes, we present Hf-time compilations from three geographically distinct Meso-to Neoproterozoic orogenic belts in the North Atlantic Region whose geodynamic configurations remain a subject of debate. We use the εHf/Ma trajectory to assist in understanding their evolution. The εHf/Ma trajectory of the Sveconorwegian Orogen corresponds to a ^(176)Lu/^(177) Hf ratio of 0.012, which implies a process driven primarily by reworking of preexisting crust that is balanced with input from the depleted mantle resulting in a relatively shallowεHf/Ma slope. The Valhalla Orogen reveals a similar comparatively shallow εHf/Ma path. In stark contrast to these patterns is the steep εHf/Ma trajectory of the Grenville Orogen that requires a mixing process involving a greater contribution of old crust of at least ～ 1.8 Ga age. The degree of reworking required to produce the εHf/Ma trend of the Grenville Orogen is co

关键词： Zircon Hf crustal evolution Grenville Sveconorwegian Valhalla

High-resolution 3D crustal S-wave velocity structure of the MiddleLower Yangtze River Metallogenic Belt and implications for its deep geodynamic setting

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Science China Earth Sciences 2019年第9期62卷 1361-1378页

作者： Song LUO Huajian YAO Qiusheng LI Weitao WANG Kesong WAN Yafeng MENG Bin LIU Laboratory of Seismology and Physics of the Earth’s Interior School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China National Geophysical Observatory at Mengcheng University of Science and Technology of China Mengcheng 233500 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geophysics Chinese Earthquake Administration Beijing 100081 China

The Middle-Lower Yangtze River Metallogenic Belt(MLYMB) is an important mineral resource region in ***-resolution crustal models can provide crucial constraints to understand the ore-forming processes and geodynamic setting in this region. Using ambient seismic noise from 107 permanent and 82 portable stations in the MLYMB and the adjacent area,we present a new high-resolution 3D S-wave velocity model of this region. We first extract 5–50 s Rayleigh wave phase velocity dispersion data by calculating ambient noise cross-correlation functions(CFs) and then use the surface wave direct inversion method to invert the mixed path travel times for the 3D S-wave velocity structure. Checkerboard tests show that the horizontal resolution of the 3D S-wave velocity model is approximately 0.5°–1.0° and that the vertical resolution decreases with increasing noise and depth. Our high-resolution 3D S-wave velocity model reveals:(1) AV-shaped high-velocity zone(HVZ) is located in the lower crust and the uppermost mantle in the study region. The western branch of the HVZ passes through the Jianghan Basin,the Qinling-Dabie orogenic belt and the Nanxiang Basin. The eastern branch, which almost completely covers the main body of the MLYMB, is located near the Tanlu Fault. The low-velocity anomalies between the western and eastern branches are located in the area of the Qinling-Dabie orogenic belt.(2) High-velocity uplifts(HVUs) are common in the crust of the MLYMB,especially in the areas near the Tanlu Fault, the Changjiang Fault and the Yangxin-Changzhou Fault. The intensities of the HVUs gradually weaken from west to east. The V-shaped HVZ in the lower crust and uppermost mantle and the HVUs in the middle and lower crust likely represent cooled mantle intrusive rocks. During the Yanshanian period, fault systems formed in the MLYMB due to the convergence between the South China Plate and the North China Plate, the multiple-direction drifting of the PaleoPacific Plate and its subd

关键词： Middle-Lower Yangtze River Metallogenic Belt Ambient noise Surface wave crustal structure Mineralization dynamics

crustal Deformation Revealed by GPS in Kumaun Himalaya,India

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Journal of Mountain Science 2014年第1期11卷 41-50页

作者： Rakesh K.DUMKA Bahadur S.KOTLIA Kireet KUMAR Gokul S.SATYAL Lalit M.JOSHI Institute of Seismological Research Centre of Advanced Study in Geology Kumaun University G.B.Pant Institute of Himalayan Environment and Development

The foremost Global Positioning System(GPS) derived measurements in the Kumaun Himalaya indicate that most of the crustal motion of the Indian plate is accommodating towards the base as well as on the hanging wall of Main Central Thrust(MCT).Deformation pattern within the Kumaun Himalaya varies from south to north and indicates maximum deformation rate near *** study,based on the campaign mode GPS survey during 2003- 2006,reveals that the area between north of North Almora Thrust(NAT) and at the base of Great Himalaya registers maximum strain rate,which is lowered towards the Trans Himadri Fault(THF).The GAMIT-GLOBK processed campaign data of the area show that currently,the Himalayan Frontal Fault(HFF) and Main Boundary Thrust(MBT) are locked with the Indian plate,and a 6.7 ± 2.5 mm/yr of horizontal shortening is taking place between the Lesser Himalaya and Peninsular India.

关键词： Kumaun Himalaya Faults thrust systems Deformation Convergence crustal strain

crustal Heat Production and Mantle Heat Flow in Southeast China

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Science China Chemistry 1994年第10期37卷 1252-1263页

作者：胡圣标汪集旸 Institute of Geology Academia SinicaBeijing 100029PRC

The correlation between seismic velocity (v_p) and radiogenic heat production (A) en- ables the distribution of crustal heat production to be evaluated,from which the mantle heat flow for 21 seismic velocity-depth profiles located along the two continental geotraverses in Southeast China can be *** approaches have been proposed to special problems connected with the conversion of seismic velocities into heat production in orogenic *** results show that the crustal heat flow in Southeast China is quite inhomogeneous,varying between 17.8 and 46 mW·m^(-2),which can be attribut- ed to the complicated crustal structure related to overthrusting and overlapping in the upper *** re- markable regional variation in the mantle heat flow,ranging from 23.2 to 41.6 mW·m^(-2),corresponds to the large-scale tectonothermal evolution of the orogenic belts.

关键词： v_p-A conversion crustal heat production mantle heat flow Southeast China

crustal Structure Revealed by a Deep Seismic Sounding Profile of Baijing-Gaoming-Jinwan in the Pearl River Delta

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Journal of Ocean University of China 2018年第1期17卷 186-194页

作者： ZHANG Xiang YE Xiuwei LV Jinshui SUN Jinlong WANG Xiaona CAS Key Laboratory of Ocean Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China Guangdong Earthquake Agency China Earthquake AdministrationGuangzhou 510070China

The Pearl River Estuary area, located in the middle part of the southern China coastal seismic belt, has long been considered a potential source of strong earthquakes above magnitude 7.0. To scientifically assess the potential strong earthquake risk in this area, a three-dimensional artificial seismic sounding experiment, consisting of a receiving array and seabed seismograph, was performed to reveal the deep crustal structure in this region. We used artificial ship-borne air-gun excitation shots as sources, and fixed and mobile stations as receivers to record seismic data from May to August 2015. This paper presents results along a line from the western side of the Pearl River Estuary to the western side of the Baijing-Gaoming-Jinwan profile. A two-dimensional velocity structure was constructed using seismic travel-time tomography. The inversion results show that the Moho depth is 27 km in the coastal area and 30 km in the northwest of the Pearl River Estuary area, indicating that the crust thins from land to sea. Two structural discontinuities and multiple low-velocity anomalies appear in the crustal section. Inside both discontinuity zones, a low-velocity layer, with a minimum velocity of 6.05 km s^(-1), exists at a depth of about 15 km, and another, with a minimum velocity of 6.37 km s^(-1), exists at a depth of about 21.5 km between the middle and lower crust. These low velocities suggest that the discontinuities may consist of partly molten material. Earthquakes with magnitudes higher than 5.0 occurred in the low-velocity layer along the profile. The deep Kaiping-Enping fault, rooted in the crust, may be one of the most important channels for deep material upwelling and is related to tectonic movement since the Cretaceous in the Pearl River Delta tectonic rift basin.

关键词： Pearl River Estuary seismic sounding profile crustal structure Kaiping-Enping fault earthquake potential

crustal structure of seismic velocity in southern Tibet and east-westward escape of the crustal material——An example by wide-angle seismic profile from Peigu Tso to Pumoyong Tso

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Science China Earth Sciences 2004年第6期47卷 500-506页

作者： S. Klemperer Department of Geophysics Stanford University Stanford CA94305-2215 USA

The reflecting events from Moho and other interfaces within the crust are recog-nized from the wavefield characteristics of P- and S-wave for the 480km long wide-angle seismic profile between Peigu Tso and Pumoyong Tso. Then, seismic crustal structures of P- and S-wave velocities and Poisson ratio under the nearly east-west profile in southern Tibet are interpreted by fitting the observed traveltimes with the calculated ones by forward modelling. Our interpreting results demonstrate that the crustal thickness varies remarkably in the east-west direction, showing a pattern that the crust could be divided into three parts bounded by the west of Dingri and the east of Dinggy? respectively, where the depth of Moho is about 71km for the western part, about 76km for the middle and about 74km for the eastern. There is one lower velocity layer (LVL) at the bottom of the upper crust with depth of 20—30 km. One of the distinct features is that the thickness of LVL abruptly thins from 24km on the west to 6km on the east. The other is that the velocity variation in the crust along east-west direction for both P- and S-wave displays a feature as quasi-periodic variation. The lower velocity (compared to the average value for the continent of the globe) in the lower crust and three sets of north-southward active normal faults are probably attributed to the coupling process of material delamination in the lower crust, crustal thicking and east-westward escape of the crustal material accompanied with the continental col-lision between India and Eurasia Plate.

关键词： southern Tibet, crustal structure, lower velocity layer,delamination, east-west escape.