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Earthquake Science 2015年第1期28卷 49-57页

作者： Songbai Xuan Chongyang Shen Hui Li Hongtao Hao School of Geodesy and geomatics Wuhan University institute of Seismology China Earthquake Administration

The 4.20 Lushan Ms7.0 earthquake occurred on the southwest segment of the Longmenshan fault on 20 April 2013. Some meaningful information on the prepa- ration and occurrence of this earthquake was found based on the dynamic variation of gravity （DVG）. To examine the great progress of the Lushan earthquake, we obtained the density variation （DENV） derived from the DVG using the compact gravity inversion method in this article. The inversion results reveal three main findings：（1） the DENV in the crust in the Jinshajiang fault area changed from positive in 2010-2011 to negative in 2011-2012. （2） The DENV in the Xianshuihe fault area decreased continuously from 2010 to 2012. （3） The DENV of the uppermost mantle of South China decreased in 2010-2011 and increased in 2011-2012. We propose that the flow/expansion of the middle-lower crust beneath the Bayan Har block and Moho subsidence on the southwest margin of the Chuan-Dian block may have been the major causes of the Lushan earthquake.

关键词： Density variations Gravity inversion Deepprogress Lushan earthquake

Lithospheric thermal and compositional structure of South China jointly inverted from multiple geophysical observations

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Science China Earth Sciences 2021年第1期64卷 148-160页

作者： Bin SHAN Wanli ZHOU Yang XIAO Hubei Subsurface Multi-Scale Imaging Key Laboratory.institute of Geophysics and geomatics China University of GeosciencesWuhan 430074China

The detailed lithospheric structure of South China is the basis for the understanding of tectonic processes of eastern ***,two essential issues in the study of lithospheric structure are the thermal and compositional structures,which are usually derived from either geophysical or geochemical ***,inversions from single geophysical or geochemical datasets have certain limitations,making it necessary to develop joint inversions of geophysical,geochemical and petrological *** this paper,through thermodynamic simulation and probabilistic inversion,we inverted multiple datasets including topography,geoid height,surface heat flow and surface wave dispersion curves for the 3D lithospheric thermal and compositional structure of South *** results reveal a thin(200 km),suggesting that the thick and cold craton lithospheric roots are *** may exist a discontinuous interface beneath the Sichuan Basin,with the saturated lower layer thicker than the refractory upper *** a result,the lithospheric mantle of the Sichuan Basin and surrounding regions is mainly composed of saturated and transitional peridotite.

关键词： South China Lithospheric thermal structure Lithospheric compositional structure Thermodynamic inversion

Some issues on 2.5-D transient electromagnetic forward

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Journal of Central South University of Technology 2005年第Z1期12卷 177-182页

作者： XIONG Bin MAO Ya-dan School of Info-Physics and geomatics Engineering Central South University Changsha 410083 China Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China

Numerical calculation for two integral transforms in 2.5-D transient electromagnetic forward is a difficult and key task, namely, the inverse Fourier transform and the inverse Laplace transform. Some effective algorithms for them were described. Based on the known algorithms in DC resistivity on wave-number distribution and selection, we proposed a principle on how to choose the least wave-number concerning the central-loop transient electromagnetic method. First, observe the behavior of transformation function curve with regard to wave-number in Fourier domain. In the light of its asymptote, ascertain the coverage scope of wave-number. Compared with analytic solution, the least wave-number in Fourier domain can be derived. Furthermore, the Laplace numerical inversion algorithm which needs only a few Laplace variables in pure real domain was also introduced here. The procedure was applied to forward modeling on transient electromagnetic field of a vertical magnetic dipole over uniform half-space to demonstrate them effectiveness and general applicability.

关键词： transient electromagnetic method 2.5-D forward modeling inverse fourier transform inverse laplace transform wave-number

Historical trends in the anthropogenic heavy metal levels in the tidal flat sediments of Lianyungang, China

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Journal of Environmental Sciences 2013年第7期25卷 1458-1468页

作者： Rui Zhang Fan Zhang Yingjun Ding Jinrong Gao Jing Chen Li Zhou School of Geodesy and geomatics Engineering Huaihai Institute of Technology State Key Laboratory of Pollution Control and Resources Reuse Nanjing University Jiangsu Marine Resources Development Research institute Huaihai Institute of Technology

The sedimentation of metals can preserve the historical record of contaminant input from local and regional sources and provide information on the historical changes in regionalwater and sediment quality. We report the 210Pb activities and the heavy metal （Cd, Cr, Cu, Mn, Pb and Zn）depth profiles from sediment cores retrieved in 2010. The mean sedimentation rates of 0.85-1.5 cm/yr aredetermined by 210 Pbdating. The sediments in the tidal flat have recorded heavy metaldeposition and thus allow the establishment of a connection between the temporal evolution of the heavy metal pollution and the historical changes in the economicdevelopment of Lianyungang. The enrichment factors （EF） are calculated to estimate the level of contamination stored in these sediments. The results show that in the studied sites, Cr and Cudisplay low EF values and are mainly from lithogenic origin. For the other studied trace metals, a great variability in the sedimentary record is observed. Significant anthropogenic enrichment over the last 50 years is revealed at the tidal flat that receives fluvial inputs. Zinc is the elementwith the highest EF values, followed by the order of Pb 〉 Cd 〉 Mn 〉 Cu and Cr. The temporal variations of the heavy metals peakduring the late 1980s to the early2000s and show adecreasing trend afterward. The pollution intensity of the tidal flat isdetermined by using EF and thegeo-accumulation index （Igeo ）,which show that, based on the Igeo scale, the tidal flat of Haizhou Bay is unpolluted to moderately polluted.

关键词： sediment rates heavy metals pollution anthropogenic input tidal flat

Inverse Spline Interpolation for All-time Resistivity of Central-Loop TEM

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Journal of China University of Mining and Technology 2005年第3期15卷 172-176页

作者： XIONG Bin MAO Ya-dan School of lnfo-Physics ＆ geomatics Engineering Central South University Changsha Hunan 410083 China institute of Geophysics ＆ geomatics China University of Geosciences Wuhan Hubei 430074 China

A convenient numerical calculation method (inverse spline interpolation) for all-time apparent resistivity intransient electromagnetic method (TEM) is proposed in this paper. Characteristic of early and late normalized inductiveelectromotive force was investigated. According to the turning point, the transient process is divided into the earlyphase, the turning point, and the late phase. Afterwards, apparent resistivity is obtained through inverse spline interpo-lation in the early and the late phases, respectively. Finally, the resistivities of the early-time and the late-time wereconnected together by the turning point. The result shows that the inverse spline method is feasible and the method alsolays a foundation for initial model construction in the TEM automatic inversion.

关键词： transient electromagnetic method all-time apparent resistivity inverse spline interpolation

GIS based integration of multi-spectral remote sensing and morphostructural analysis for delineating potential areas of hydrocarbon exploration in Western Vindhyan Basin,India

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Energy Geoscience 2022年第2期3卷 191-201页

作者： Subhobroto Mazumde Ashish Misra Remote Sensing&geomatics KDM Institute of Petroleum ExplorationOil and Natural Gas Corporation LimitedIndia

The Chambal Valley forms the western part of the Proterozoic Vindhyan Basin that has been less studied and poorly explored from the hydrocarbon perspective than its eastern counterpartdthe Son Valley *** the present manuscript,attempts have been made to use remote sensing and GIS(geographic information system)based analysis to focus on the northern part of Chambal Valley to decipher its tectonics and structural configuration,its tectonic relation with the Son Valley Vindhyans,Bundelkhand Massif and Ganga *** study also assumes significance as it attempts to delineate potential lead areas for hydrocarbon exploration in Chambal *** part of the study,a detailed spectral analysis based on image data sets is carried out to identify areas of microseeps as proxies of potential hydrocarbon ***,a neotectonics-based geomorphic analysis is carried out to delineate a fault network and geomorphic highs that act as aliases to subsurface faults and structural *** results are subsequently validated by available geophysical data and extensive fieldwork,and suggest four structural trends in the Chambal Valley as striking NE-SW,E-W,NW-SE and NeS,of which the NW-SE trend is the oldest,followed by the NE-SW,E-W and NeS trends.A GIS-based analysis of the E-W trends indicates that these are probably manifestations of the westward continuity of E-W-trending shear zones developed in Bundelkhand massif within the basement of the Chambal *** remote sensing studies of the shear zone network exposed in the Bundelkhand massif indicate the pattern to be replicated on a larger scale in the morphostructural fault layout in the adjacent Ganga Basin,implying these shear zones may be continuing in the basement of Ganga Basin and controlling structures developed later,and consequently the different petroleum system elements in the basin.A dip data based structural analysis of the Chambal Valley describes a regional synform attributed with an almost

关键词： Chambal Vindhyans Hydrocarbon Remote sensing Shear zone Syncline

Mapping cultural ecosystem services in mountain forests using mobile phone data

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Journal of Mountain Science 2023年第12期20卷 3437-3449页

作者： CIESIELSKI Mariusz KAMINSKA Agnieszka Department of geomatics Forest Research InstituteSękocin StaryBraci leśnej 305-090Poland

The aim of the work was to determine the spatial distribution of activity in the forest on the area of the Forest Promotional Complex“Sudety Zachodnie”using mobile phone *** study identified the sites with the highest(hot spot)and lowest(cold spot)***,stand,demographic,topographic and spatial factors affecting the distribution of activity were also *** approaches were applied in our research:global and local Moran’s coefficients,and a machine learning technique,Boosted Regression *** results show that 11,503,320 visits to forest areas were recorded in the“Sudety Zachodnie”in *** most popular season for activities was winter,and the least popular was *** global and local Moran’s I coefficients,three small hot clusters of activity and one large cold cluster were *** with high values with similar neighbours(hot-spots)were most often visited forest areas,averaging almost 200,000 visits over *** fewer visits were recorded in cold-spots,the average number of visits to these areas was about 4,*** value of global Moran’s I was equal to 0.54 and proved significant positive spatial *** of Boosted Regression Trees modeling of visits in forest,using tree stand habitat and spatial factors accurately explained 76%of randomly selected input *** variables that had the greatest effect on the distribution of activities were the density of hiking and biking trails and diversity of *** methodology presented in this article allows delineation of Cultural Ecosystem Services hot spots in forest areas based on mobile phone *** also allows the identification of factors that may influence the distribution of visits in *** data are important for managing forest areas and adapting forest management to the needs of society while maintaining ecosystem stability.

关键词： Ecosystem services Big data Traffic research Monitoring Forests

How to Effectively Prevent and Mitigate Geomagnetic Hazard?

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Journal of Earth Science 2023年第4期34卷 1304-1305页

作者： Xiangyun Hu Bo Han Tao Yu institute of Geophysics&geomatics China University of GeosciencesWuhan 430074China institute of Geological Survey China University of GeosciencesWuhan 430074China

Compared to well-known geological hazards such as earthquakes, volcanic eruptions, landslides, and mudslides, the concept of “geomagnetic hazards” is much less familiar to people. Geomagnetic hazards are intense disturbances in the Earth’ s magnetic field caused by solar flares, which can lead to geomagnetic storms. These storms ignite large geomagnetic induction currents and disrupt the global upper atmospheric and ionospheric environment.

关键词： storm geomagnetic volcanic

A comparative analysis of five global cropland datasets in China

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Science China Earth Sciences 2016年第12期59卷 2307-2317页

作者： LU Miao WU WenBin ZHANG Li LIAO AnPing PENG Shu TANG HuaJun Key Laboratory of Agri-informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences National geomatics Centre of China

Accurate information of cropland area and spatial location is critical for studies of national food security, global environmental change, terrestrial ecosystem geophysics and the geochemical cycle. In this paper, we compared five global cropland datasets in circa 2010 of China from in terms of cropland area and spatial location, including Global Land30, FROM-GLC, Glob Cover, MODIS Collection 5, and MODIS Cropland. The results showed that the accuracies of cropland area and spatial location of Globe Land30 were higher than the other four products. The cropland areas of the five products varied in most of the provinces. Compared with the statistical data, the best goodness of fit was obtained using Globe Land30, followed by MODIS Collection 5 and FROM-GLC, with MODIS Cropland and Glob Cover having the poorer accuracies. Regarding the spatial location of cropland, Globe Land30 achieved the best accuracy, followed by FROM-GLC and MODIS Collection 5, with Glob Cover and MODIS Cropland having the poorer accuracies. In addition, the spatial agreement of the five datasets was reduced from agricultural production area to pastoral area and significantly affected by elevation and slope factors. Although the spatial resolution of MODIS Collection 5 was the lowest, accuracies of the cropland area and spatial location were better than those of Glob Cover and MODIS Cropland. Therefore, high spatial resolution remote sensing images can help to improve the accuracy of the dataset during land cover mapping, while it is also important to select a suitable classification method. Furthermore, in northwestern and southeastern China, spectral mixing pixels are universal because of the complicated landscape and fragmentized topography and result in uncertainty and poor consistency when using the five products. Therefore, these regions require additional attention in future cropland mapping studies.

关键词： Land cover Cropland area Spatial location Accuracy Spatial agreement

A hydrothermal investigation system for the Qianlong-Ⅱ autonomous underwater vehicle

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Acta Oceanologica Sinica 2019年第3期38卷 159-165页

作者： Tao Wu Chunhui Tao Jinhui Zhang Ao Wang Guoyin Zhang Jianping Zhou Xianming Deng Key Laboratory of Submarine Geosciences Second Institute of Oceanography Ministry of Natural Resources School of Oceanography Shanghai Jiaotong University institute of Geophysics and geomatics China University of Geosciences

Qianlong-Ⅱ is a fully autonomous underwater vehicle designed for the investigation of submarine resources,particularly polymetallic sulfides. It was used to successfully explore hydrothermal fields on the Southwest Indian Ridge. Here, we summarized the exploration of hydrothermal systems using Qianlong-Ⅱ, including detailed descriptions of its implementation along with the systems used for data management and fast mapping. We also introduced a method to remove platform magnetic interference using magnetic data while Qianlong-Ⅱ is spinning. Based on hydrothermal anomalies collected by Qianlong-Ⅱ, we developed a rapid method for locating hydrothermal vents. Taking one dive as an example, we systemically demonstrated the process for analyzing hydrothermal survey data to locate hydrothermal vents.

关键词： Qianlong-Ⅱ autonomous underwater vehicle data management hydrothermal investigation