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Quantitative algorithm for airborne gamma spectrum of large sample based on improved shuffled frog leaping-particle swarm optimization convolutional neural network

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Nuclear Science and Techniques 2023年第7期34卷 242-252页

作者： Fei Li Xiao-Fei Huang Yue-Lu Chen Bing-Hai Li Tang Wang Feng Cheng Guo-Qiang Zeng Mu-Hao Zhang College of Nuclear technology and Automation Engineering Chengdu University of TechnologyChengdu 610000China Applied Nuclear technology in Geosciences key laboratory of Sichuan Province Chengdu 610000China airborne survey and remote sensing Center of Nuclear Industry Shijiazhuang 050000China hebei key laboratory of airborne Detection and remote sensing technology Shijiazhuang 050000China

In airborne gamma ray spectrum processing,different analysis methods,technical requirements,analysis models,and calculation methods need to be *** meet the engineering practice requirements of airborne gamma-ray measurements and improve computational efficiency,an improved shuffled frog leaping algorithm-particle swarm optimization convolutional neural network(SFLA-PSO CNN)for large-sample quantitative analysis of airborne gamma-ray spectra is proposed *** method was used to train the weight of the neural network,optimize the structure of the network,delete redundant connections,and enable the neural network to acquire the capability of quantitative spectrum *** full-spectrum data processing,this method can perform the functions of energy spectrum peak searching and peak area *** network training,the mean SNR and RMSE of the spectral lines were 31.27 and 2.75,respectively,satisfying the demand for noise *** test the processing ability of the algorithm in large samples of airborne gamma spectra,this study considered the measured data from the Saihangaobi survey area as an example to conduct data spectral *** results show that calculation of the single-peak area takes only 0.13~0.15 ms,and the average relative errors of the peak area in the U,Th,and K spectra are 3.11,9.50,and 6.18%,indicating the high processing efficiency and accuracy of this *** performance of the model can be further improved by optimizing related parameters,but it can already meet the requirements of practical engineering *** study provides a new idea for the full-spectrum processing of airborne gamma rays.

关键词： Large sample airborne gamma spectrum(AGS) Shuffled frog leaping algorithm(SFLA) Particle swarm optimization(PSO) Convolutional neural network(CNN)

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Characteristics of fault structures in the south coastal zone of Taizhou based on aeromagnetic data

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Applied Geophysics 2020年第5期17卷 719-735,901页

作者： Ming Wang Shengjun Liang Jiaojiao Li Xiaoxing Lin Yongjun Zhang China Aero Geophysical survey and remote sensing Center for Natural Resources BeijingPRC key laboratory of airborne Geophysics and remote sensing Geology of MNR BeijingPRC

The south coastal of Taizhou lies on the magmatic rock belt along the southeast coast of China,which has a complex regional geological structures,intense tectonic movement,and frequent magmatic *** the basis of the latest aeromagnetic data,combined with regional geology,gravity,and magnetic susceptibility information,integrated interpretation of the regional aeromagnetic anomalies and their refl ected faults was *** to the block features in diff erent zones of the reduction to the pole aeromagnetic data,the magnetic field characteristics and relationship with the structure division were described in *** different characteristics of the magnetic field are the concentrated reflection of tectonic movements,magmatic activities,and stratigraphic distributions;the fault structure,especially deep and large fault structures,was inferred and *** fault structures were mainly distributed in the NE,NNE,and NW directions,with approximately equal spacing between *** magnetic anomaly is mainly characterized by the boundary,gradient zones,and beaded anomalies in a different magnetic *** faults are not only important tectonic boundaries in this region but also tectonic belts that control the distribution of *** the interaction of these faults,they form the basic structural pattern of the east-west zone and the north-south *** NE faults have the largest scale and obviously control the diff erent magnetic fi elds and magmatic *** results can provide a reference for further study of the distribution and activity characteristics of magmatic rocks in the coastal zone.

关键词： aeromagnetic data magnetic field characteristics fault structure features the south of Taizhou the coastal zone

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remote sensing-based dynamic monitoring and environmental change of wetlands in southern Mongolian Plateau in 2000‒2018

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China Geology 2021年第2期4卷 353-363页

作者： Wen-hui Jie Chun-lei Xiao Ce Zhang En Zhang Jing-yue Li Bing Wang Hai-wei Niu Shuang-fa Dong airborne survey and remote sensing Center of Nuclear Industry Shijiazhuang 050002China hebei key laboratory of airborne survey and remote sensing technology Shijiazhuang 050002China China Aero Geophysical survey and remote sensing Center for Natural Resources China Geological SurveyBeijing 100083China

The environmental change in the wetlands in the southern Mongolian Plateau has important impacts on the environment of North China and even the entire Northeast Asia,from which the global climate change can be understood on a large scale,especially the climate change in the Mongolian *** study extracted the information on the wetlands from three stages of remote sensing images(also referred to as RS images)of the study area,including Enhanced Thematic Mapper Plus(ETM+)images of 2000,TM images of 2010,and Landsat 8 Operational Land Imager(OLI)images of *** indicated by the extraction results,the area of wetlands decreased from 796.90 km^(2) of 2000 to 666.24 km^(2) of 2018 at a rate of 7.26 km^(2)/*** reduced area is 130.66 km^(2),which is about 16.4%*** the patch number of wetlands decreased from 731 of 2000 to 316 of 2018 in the study area,approximately 56.8%reduction(415 patches),and the decrease in the area of the wetlands mainly occurred in the northwest endorheic *** terms of wetland types,the change of the wetlands was dominated by the decrease of lacustrine wetlands,of which the area and patch number decreased by 106.2 km^(2) and 242,***,the area of the lacustrine wetlands decreased at the highest rate of 8.70 km^(2)/a in 2010‒*** the perspective of spatial distribution,the wetlands in the western part shrunk more notably than those in the eastern part as a whole in the study *** to local meteorological data,the precipitation gently decreased and the temperature increased(about 1.7℃)from ***,the decrease in the area of the wetlands and the temperature rises in the study area were mainly driven by the Mongolian monsoon climate,reduction in precipitation,and human activities.

关键词： Wetlands Environmental change Global climate change remote sensing Dynamic monitoring Southern Mongolian Plateau

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Transformations between Aeromagnetic Gradients in Frequency Domain

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Journal of Earth Science 2010年第1期21卷 114-122页

作者：李海侠徐世浙余海龙魏巍房江奇 Department of Earth Sciences Zhejiang University Department of Earth Sciences Kunming University of Science and Technology airborne survey and remote sensing Center of Nuclear Industry

Aeromagnetic gradients are often used to enhance details or add new insights for interpretation. The gradients may be measured or derived from the total field or from transformation between horizontal and vertical gradients. At present, vertical, horizontal, and triaxial aeromagnetic gradiometers are in operation throughout the world, while the first two are used more widely. Transformations between horizontal and vertical gradients are needed for acquiring three gradient components or for checking the validity of measured gradients. Transformation of potential field by fast Fourier transform technique in frequency domain is popularly used; however, when applied to transforming between gradients, there is a problem that needs resolving. Because those expressions of transform operators are undefined when u or v is equal to zero or u and v are simultaneously equal to zero （u is the frequency in x-direction, and v is the frequency in y-direction）, the operators cannot be sampled at these frequencies. Consequently, the transformation cannot be implemented by fast Fourier transform technique directly. In this article, shift sampling theory is employed for resolving this problem. Model test results show that the technique has good accuracy, and the real case of transformation indicates that the computed results agree better with the measured gradients; it demonstrates not only the effective- ness of method but also the reliability of the measured gradients.

关键词： frequency domain horizontal gradient vertical gradient transformation shift sampiing theory.

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Expansion of the South China Sea basin:Constraints from magnetic anomaly stripes,sea floor topography,satellite gravity and submarine geothermics

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Geoscience Frontiers 2017年第1期8卷 151-162页

作者： Xuezhong Yu Chunji Xue Haigang Shi Weiping Zhu Yinghui Liu Hang Yin State key laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of CeosciencesBeijing 100083China China Aero Geophysical survey and remote sensing Center for Land and Resources Beijing 100083China airborne survey and remote sensing Center of Nuclear Industry Shijiazhuang 050002China

The widely distributed E-W-trending magnetic anomaly stripes in the central basin and the N-Etrending magnetic anomaly stripes in the southwest sub-basin provide the most important evidence for Neogene expansion of the South China *** expansion mechanism remains,however,controversial because of the lack of direct drilling data,non-systematic marine magnetic survey data,and irregular magnetic anomaly stripes with two obvious *** example,researchers have inferred different ages and episodes of expansion for the central basin and southwest *** controversy centers on the order of basinal expansion and the mechanism of expansion for the entire South China Sea *** study attempts to constrain these problems from a comprehensive analysis of the seafloor topography,magnetic anomaly stripes,regional aeromagnetic data,satellite gravity,and submarine *** mapped seafloor terrain shows that the central basin is a north-south rectangle that is relatively shallow with many seamounts,whereas the southwest sub-basin is wide in northeast,gradually narrows to the southwest,and is relatively deeper with fewer *** magnetic anomaly stripes are present in the central basin with variable dimensions and directions that are dominantly EWtrending,followed by the NE-,NW- and *** such stripes are few in the southwest sub-basin and mainly *** magnetic data suggest that the NW-trending Ailaoshan-Red River fault extends into the South China Sea,links with the central fault zone in the South China Sea,which extends further southward to Reed *** gravity data show that both the central basin and southwest sub-basin are composed of oceanic *** Changlong seamount is particularly visible in the southwest sub-basin and extends eastward to the Zhenbei *** a low gravity anomaly zone coincides with the central fault zone in the *** submarine geothermic distribution demonstra

关键词： Ages of spreading Expansion mode Expansion mechanism South China Sea

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Research achievements of the Qinghai-Tibet Plateau based on 60 years of aeromagnetic surveys

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China Geology 2021年第1期4卷 147-177页

作者： Sheng-qing Xiong China Aero Geophysical survey and remote sensing Center for Natural Resources China Geological SurveyBeijing 100083China key laboratory of airborne Geophysics and remote sensing Geology Ministry of Natural ResourcesBeijing 100083China

The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral *** paper reviews the aeromagnetic surveys in the Plateau in the past 60 years and summarizes relevant research achievements,which mainly include the followings.(1)The boundaries between the Plateau and its surrounding regions have been *** detail,its western boundary is restricted by West Kunlun-Altyn Tagh arc-shaped magnetic anomaly zone forming due to the arc-shaped connection of the Altyn Tagh and Kangxiwa faults and its eastern boundary consists of the boundaries among different magnetic fields along the Longnan(Wudu)-Kangding ***,the fault on the northern margin of the Northern Qilian Mountains serves as its northern boundary.(2)The Plateau is mainly composed of four orogens that were stitched together,namely East Kunlun-Qilian,Hoh-Xil-Songpan,Chamdo-Southwestern Sanjiang(Nujiang,Lancang,and Jinsha rivers in southeastern China),and Gangdese-Himalaya orogens.(3)The basement of the Plateau is dominated by weakly magnetic Proterozoic metamorphic rocks and lacks strongly magnetic Archean crystalline basement of stable continents such as the Tarim and Sichuan ***,it exhibits the characteristics of unstable orogenic basement.(4)The Yarlung-Zangbo suture zone forming due to continent-continent collisions since the Cenozoic shows double aeromagnetic anomaly ***,it can be inferred that the Yarlung-Zangbo suture zone formed from the Indian Plate subducting towards and colliding with the Eurasian Plate twice.(5)A huge negative aeromagnetic anomaly in nearly SN trending has been discovered in the middle part of the Plateau,indicating a giant deep thermal-tectonic zone.(6)A dual-layer magnetic structure has been revealed in the *** consists of shallow magnetic anomaly zones in nearly EW and NW trending and deep magnetic anomaly zone

关键词： Aeromagnetic survey Tectonic framework Suture zone Fault Magnetic rocks Uplift Oil and gas resource assessment Ore prospecting Qinghai-Tibet Plateau

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Late Triassic Intracontinental Deformation of South Tianshan,Central Asia:Evidence from Syn-tectonic Sedimentation and Detrital Zircon Provenances of the Kuqa Depression

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 548-568页

作者： QIN Xiang CHEN Xuanhua SHAO Zhaogang ZHANG Yiping WANG Yongchao LI Bing SU He WANG Ye LIU Kui HAN Lele China Aero Geophysical survey and remote sensing Center for Natural Resources Beijing 100083China key laboratory of airborne Geophysics and remote sensing Geology MNRBeijing 100083China Chinese Academy of Geological Sciences Beijing 100037China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China

The Tianshan range,a Paleozoic orogenic belt in Central Asia,has undergone multiple phases of tectonic activities characterized by the N-S compression after the early Mesozoic,including the far-field effects of the Cenozoic Indian-Asian ***,there are limited reports on the tectonic deformation and initiation of Triassic intracontinental deformation in the Tianshan *** this structural context is crucial for interpreting the early intracontinental deformation history of the Eurasian continent during the early *** strata and syn-tectonic sediments provide a rich source of information on tectonic activities and have been extensively used in the studies of orogenic *** on detail fieldwork conducted in this study,the middle-late Triassic Kelamayi Formation of the northern Kuqa Depression in the southern Tianshan fold-thrust belt has been identified as the typical syn-tectonic growth *** youngest detrital zircon component in two lithic sandstone samples from the bottom and top of the Kelamayi growth strata yielded U-Pb ages of 223.4±3.1 and 215.5±2.9 Ma,respectively,indicating that the maximum depositional age of the bottom and top of the Kelamayi growth strata is 226-220 and 218-212 *** geochronological distribution of detrital samples from the Early-Middle Triassic and Late Triassic revealed abrupt changes,suggesting a new source supply resulting from tectonic activation in the Tianshan *** coupling relationship between the syn-tectonic sedimentation of the Kelamayi Formation and the South Tianshan fold-thrust system provides robust evidence that the Triassic intracontinental deformation of the South Tianshan range began at approximately 226-220 Ma(during the Late Triassic)and ended at approximately 218-212 *** findings provide crucial constraints for understanding the intraplate deformation in the Tianshan range during the Triassic.

关键词： growth strata basin-mountain coupling Triassic Indosinian event Kuqa Depression South Tianshan

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A mathematical morphology-based multi-level filter of LiDAR data for generating DTMs

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Science China(Information Sciences) 2013年第10期56卷 144-157页

作者： CHEN Dong ZHANG LiQiang WANG Zhen DENG Hao State key laboratory of remote sensing Science Beijing Normal University

Light detecting and ranging(LiDAR)technology has become an efective way to generate highresolution digital terrain models(DTMs).To generate DTMs,point measurements from non-ground features,such as buildings,vegetation and vehicles,have to be identifed and removed while preserving the terrain *** paper proposes an efcient mathematical morphology-based multi-level flter to generate DTMs from airborne LiDAR *** non-ground points are frst identifed with the characteristics of the multiecho airborne LiDAR *** localized mathematical morphology opening operations are then immediately applied to the remaining *** gradually increasing the window size of the flter and using a dynamic critical gradient threshold,the non-ground points are removed,while the ground points are *** samples were chosen from eight sites provided with the ISPRS Commission III,Working Group 3,to evaluate the accuracy of our *** the qualitative and quantitative experiment analyses show that our morphologybased multi-level flter method achieves promising results,not only in flat urban areas but also in rural areas,especially in preserving complex terrain details,while non-ground spatial objects are removed.

关键词： LiDAR mathematical morphology multi-level flter DTMs

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Evaluation on the Two Filling Functions for the Recovery of Forest Information in Mountainous Shadows on Landsat ETM + Image

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Journal of Mountain Science 2011年第3期8卷 414-426页

作者： SHAHTAHMASSEBI Amir reza MOORE Nathan Institute of Agriculture remote sensing and Information technology Zhejiang University key laboratory of Agricultural remote sensing and Information System of Zhejiang Province Department of Geography Michigan State University

In general,topographic shadow may reduce performance of forest mapping over mountainous regions in remotely sensed *** this paper,information in shadow was synthesized by using two filling techniques,namely,roifill and imfill,in order to improve the accuracy of forest mapping over mountainous *** two methods were applied to Landsat Enhanced Thematic Mapper (ETM +) multispectral image from Dong Yang County,Zhejiang Province,*** performance of these methods was compared with two conventional techniques,including cosine correction and multisource *** results showed that by applying filling approaches,average overall accuracy of classification was improved by 14 ***,through conventional methods this value increased only by 9 *** results also revealed that estimated forest area on the basis of shadow-corrected images by 'roifill' technique was much closer to the survey data compared to traditional *** from this finding,our finding indicated that topographic shadow was an accentuated problem in medium resolution images such as Landsat ETM+ over mountainous regions.

关键词： Shadow Imfill: Roifill: Landsat ETM+

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Identifying the spatio-temporal variability of human activity intensity and associated drivers: a case study on the Tibetan Plateau

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Frontiers of Earth Science 2022年第3期16卷 744-756页

作者： Cai LIU Haiyan ZHANG Fuping GAN Yunge LU Hao WANG Jiahong ZHANG Xing JU College of Earth Sciences Chengdu University of TechnologyChengdu 610059China key laboratory of airborne Geophysics and remote sensing Geology(Ministry of Nature Resources) Beijing 100083China China Aero Geophysical survey and remote sensing Center for Natural Resources Beijing 100083China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Human activities have significantly degraded ecosystems and their associated *** understanding the spatio-temporal variability and drivers of human activity intensity(HAI),we can better evaluate the interactions between human and terrestrial ecosystems,which is essential for land-use related decision making and eco-environmental *** the“third pole,”the Tibetan Plateau(TP)plays a strong role in shaping the global environment,and acts as an important ecological security barrier for *** on land-use/cover change data,environmental geographic data,and socioeconomic data,we adopted a method for converting different land use/cover types into construction land equivalent to calculate the HAI value and applied the Getis-Ord Gi*statistic to analyze the spatio-temporal dynamics associated with HAI since 1980 on the ***,we explored the forces driving the HAI changes using GeoDetector software and a correlation *** main conclusions are as follows:It was observed that HAI increased slowly from 3.52%to 3.65%during the 1980-2020 period,with notable increases in the western part of the Qaidam Basin and Hehuang ***,HAI was associated with a significant agglomeration effect,which was mainly concentrated in the regions of the Yarlung Zangbo and Yellow-Huangshui *** natural and anthropogenic factors were identified as important driving forces behind the spatial changes in HAI,of which soil type,gross domestic product,and population density had the greatest ***,the temporal changes in HAI were largely driven by economic *** information provides crucial guidance for territory development planning and ecological-protection policy decisions.

关键词： Tibetan Plateau human activity intensity GeoDetector spatio-temporal variability driving factors

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