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Unsupervised change detection of man-made objects using coherent and incoherent features of multi-temporal SAR images

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Journal of Systems Engineering and Electronics 2022年第4期33卷 896-906页

作者： FENG Hao WU Jianzhong ZHANG Lu LIAO Mingsheng State Key Laboratory of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China Key Laboratory of land subsidence Monitoring and Prevention Ministry of Land and ResourcesShanghai 200072China Shanghai Engineering Research center of land subsidence Shanghai 200072China Shanghai Institute of geological survey Shanghai 200072China

Constrained by complex imaging mechanism and extraordinary visual appearance,change detection with synthetic aperture radar(SAR)images has been a difficult research topic,especially in urban *** existing studies have extended from bi-temporal data pair to multi-temporal datasets to derive more plentiful information,there are still two problems to be solved in practical ***,change indicators constructed from incoherent feature only cannot characterize the change objects ***,the results of pixel-level methods are usually presented in the form of the noisy binary map,making the spatial change not intuitive and the temporal change of a single pixel *** this study,we propose an unsupervised man-made objects change detection framework using both coherent and incoherent features derived from multi-temporal SAR *** coefficients of variation in timeseries incoherent features and the man-made object index(MOI)defined with coherent features are first combined to identify the initial change ***,an improved spatiotemporal clustering algorithm is developed based on density-based spatial clustering of applications with noise(DBSCAN)and dynamic time warping(DTW),which can transform the initial results into noiseless object-level patches,and take the cluster center as a representative of the man-made object to determine the change pattern of each *** experiment with a stack of 10 TerraSAR-X images in Stripmap mode demonstrated that this method is effective in urban scenes and has the potential applicability to wide area change detection.

关键词： change detection multi-temporal synthetic aperture radar(SAR)data coherent and incoherent features clustering

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Detrital Zircon U-Pb Geochronology from Greywackes in the Niujuanzi Ophiolitic Mélange, Beishan Area, NW china: Provenance and Tectonic Implications

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Journal of Earth Science 2018年第1期29卷 103-113页

作者： Shengdong Wang Kexin Zhang Bowen Song Shucai Li Jianxing Li Jiyuan Yu Jianjun Bu Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological Sciences Langfang 065000 China Institute of geological survey China University of Geosciences Wuhan 430074 China State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Wuhan 430074 China Cores and Samples center of land and Resources China Geological Survey Langfang 065201 China Xi'an center of geological survey Geological Survey of China Xi'an 710000 China Wuhan center of geological survey Geological Survey of China Wuhan 430205 China

The Niujuanzi ophiolitic m^lange represents the remnant of oceanic crust between the Dunhuang massif and Mingshui-Hanshan massif. Greywacke from different tectonic slices in the Niu- juanzi ophiolitic mdlange were analyzed for detrital zircon U-Pb geochronology, trace dements and whole-rock trace elements to infer their provenance and the evolution of the Niujuanzi Ocean. Sample N-76s containing Carboniferous spores has the youngest zircon age of 323 Ma, while sample N-85s without fossils has the youngest zircon age of 449 Ma. The two samples were deposited no earlier than 323 and 449 Ma, respectively. The greywackes are depleted in large ion lithophile elements, and are relatively enriched in high field strength elements. The age spectra and trace element concentrations indicate that the sediments may have been deposited near the trench. The Hf, U, and Yb contents of zircons from sample N-76s vary widely, whereas those from sample N-85s have a narrow range. Sample N-76s contains both continental and oceanic zircons, while sample N-85s contains only continental zir-cons. The sediments were derived from the continental arc and accretionary wedge. The Paleozoic oce- anic crust zircons have ages of 430-500 Ma, indicating the timing of the expansion of the Hongliuhe- Niujuanzi-Xichangjing Ocean expansion. The oldest Paleozoic continental zircon has an age of 470 Ma, suggesting that the northward subduction of the oceanic crust may have started at that time.

关键词： detrital zircon U-Pb geochronology Niujuanzi ophiolitic melange Beishan.

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Synthesis and enhanced luminescence properties of double perovskite NaLa0.95-xYxEu0.05MgWO6 phosphors

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Rare Metals 2020年第8期39卷 895-901页

作者： Jing Zhang Jia-Lin Shen Nai-Cen Xu Nanjing center China Geological SurveyNanjing 210016China Supervision and Testing center of East china Mineral Resources of the Ministry of Land and ResourcesNanjing 210016China

Double perovskite Na(La,Y)MgWO6:Eu3+phosphors were obtained by the sol-gel method.X-ray diffractometer(XRD)patterns,scanning electron microscopy(SEM)images and photoluminescence properties were carried out to study the effect of polyethylene glycol(PEG).Enhanced optical properties were obtained by adding 3 wt%PEG under the excitation of 395 nm.Y3+with smaller radius was selected to substitute La3+in this host to decrease the symmetry and further enhance the luminescence *** Y3+concentration increasing,Na2WO4 and Y30W8O69 phases came *** emission spectra showed different shapes,and the emission intensity was enhanced by doping Y3+.Under the excitation of 395 and 465 nm,the emission intensity reached the *** Commission Internationale de L’Eclairage(CIE)coordinates of the phosphors were on the edge of the CIE diagram,illustrating that this double perovskite phosphor showed good color *** luminescence properties showed that the synthesized phosphors had great potential in solid-state lighting.

关键词： Double perovskite Structure evolution Phosphors White light emitting diodes

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The Late Cretaceous Crustal Magmatism of the Geza Arc Metallogenic Belt in Yunnan Province,and Zircon Ages and Hf Isotopic Evidence of the Porphyry Cu-Mo Mineralization

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 355-356页

作者： YANG Fucheng LI Wenchang LIU Xuelong WANG Shuaishuai Faculty of land and Resource Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China Chengdu geological survey center of china geological survey Chengdu 610081 Sichuan China

Objective The Geza arc in Yunnan Province,located in the southern Yidun arc,is an important part of the Sanjiang tectonic-magmatic belts in southwestern china and is a newly discovered copper polymetallic ore-concentrating *** studies show that the newly discovered Yanshanian porphyry Cu-Mo polymetallic mineralization superimposed in the Indosinian porphyry copper belt in this area.

关键词： Hf The Late Cretaceous Crustal Magmatism of the Geza Arc Metallogenic Belt in Yunnan Province,and Zircon Ages and Hf Isotopic Evidence of the Porphyry Cu-Mo Mineralization Mo Cu

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Risk-based evaluation on geological environment carrying capacity of mountain city - A case study in Suide County, Shaanxi Province, china

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Journal of Mountain Science 2018年第12期15卷 2730-2740页

作者： WANGYao ZHANG Mao-sheng XUE Qiang WU Si-duo Development Research center of china geological survey Beijing 100037China Xi'an center of geological survey China Geological SurveyXi'an jiooooChina East china Normal University Shanghai 200062China

With the rapid development and expansion of the cities in china, the carrying capacity of resource and environment has become a huge concern for local governments. From the perspective of geological environment, geological disasters are the main restraining factor of the development in mountain cities. This study was conducted in Suide County of Shaanxi Province with a risk-based approach as followed: a hazard analysis on geological disasters based on a slope geological survey at a scale of 1:10,000; a consequence analysis based on unmanned aerial vehicle(UAV) aerial survey data; integrating the results of hazard analysis and consequence analysis, a risk zonation and analysis of geological disasters in urban areas were completed considering urban planning, land use planning and the safety of infrastructure and major engineering. Subsequently, taking the acceptable levels of human life and property risks incurred by landslides as the criteria of the evaluation of geological environment carrying capacity, a comprehensive assessment of current and future urban carrying capacity was conducted based on the results of the risk analyses. Accordingly, the prior development zone, the restricted development zone and the prohibited zone were delineated, with corresponding suggestions for future urban development. The technological and methodological system used in the study can be applied to geological environment carrying capacity evaluation of other important mountain cities, which can provide scientific basis for the optimization of land and space.

关键词： Mountain cities Risks geological environment Carrying capacity Evaluation

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Science china(Information Sciences) 2016年第11期59卷 220-223页

作者： Zhangbing ZHOU Zehui CHENG Yueqin ZHU School of Information Engineering China University of Geosciences (Beijing) Development Research center of china geological survey and Key Laboratory of Geological Information TechnologyMinistry of Land and Resources

This article proposes to identify and recommend scientific workflows for reuse and ***, a scientific workflow is represented as a layer hierarchy that specifies the hierarchical relations between this workflow, its sub-workflows, and activities. Semantic similarity is calculated between layer hierarchies of workflows. A graph-skeleton based clustering technique is adopted for grouping layer hierarchies into *** in each cluster are identified, which serve as core workflows in this cluster, for facilitating the cluster identification and workflow ranking and recommendation with respect to the requirement of scientists.

关键词： scientific workflow reuse and repurposing layer hierarchy graph-skeleton recommendation

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Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4, SUN Yangui5, WEI Xiangdong3 & XING Zuoyun6 1. Division of Granite Geology, china geological survey, Yichang 443003, china 2. Information center of Ministry of land and Resources, Beijing 100812, china 3. geological survey of Henan Province and Institute of geological Research of Henan Province, Zhengzhou 450053, china 4. geological Institute, china Seismological Bureau, Beijing 100029, china 5. geological survey Institute of Qinghai Province, Xining 810032, china 6. china University of Geosciences, Wuhan 430074, china Division of Granite Geology China Geological Survey Yichang China Information center of Ministry of land and Resources Beijing China geological survey of Henan Province and Institute of geological Research of Henan Province Zhengzhou China geological Institute China Seismological Bureau Beijing China geological survey Institute of Qinghai Province Xining China china University of Geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

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Zircon U-Pb Geochronology and Geochemistry of the Middle Permian Siliceous Clastics and Basalt from Central Qiangtang, Northern Tibet: Implications for the Evolution of Permian

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Journal of Earth Science 2019年第2期30卷 286-295页

作者： Xueren Li Jian Wang Chinese Academy of geological Sciences china University of Geosciences Key Laboratory for Sedimentary Basin and Oil and Gas Resources Ministry of Land and Resources Chengdu center of china geological survey

In this study, we report zircon U-Pb age and geochemical data on the Middle Permian siliceous clastics and basalt samples of Lugu Formation collected in the Yaqu region from central Qiangtang. Combined with the published data, we establish the spatial and temporal evolution of the rift in central Qiangtang from the Early to Late Permian. Zircon U-Pb dating by LA-ICP-MS yields a concordant age with a weighted mean 206 Pb/238 U age of 266.6±2.8 Ma(n=6, MSWD=0.55) for the basalt. The results of detrital zircons from the siliceous clastics exhibit a prominent population of 257–270 Ma with a maximum depositional age of 265.4±2.6 Ma(n=19, MSWD=2.7) and three minor populations with peak ages of 450, 700–800, 1 800 Ma, as well as one older age of 2 039 Ma, generally coinciding with the geological events that occurred at different epochs in Qiangtang. The basalts display enrichments in highfield-strength elements(HFSE) such as Th, Ta and Hf, but show relative depletion in large-ion-lithophile elements(LILE) such as Ba, K and Sr, as well as slight depletion in Nb and exhibiting no Eu anomalies. All the samples are distributed in the within-plate setting on the Zr vs. Zr/Y and Th/Hf vs. Ta/Hf discrimination diagrams. The integration of these new data together with the regional geological background indicates that the Lugu Formation was formed in a continental rift-related setting of the central Qiangtang terrane during the Middle Permian. We propose a temporal and spatial framework that the continental rift opened as a result of the break-up of Gondwana during the Early Permian, ran to its peak in the Middle Permian and closed in the Late Permian(290–257 Ma), which could be a key constraint on the Permian evolution of Qiangtang.

关键词： zircon U-Pb siliceous clastics basalt Qiangtang Middle Permian

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Mineral Prospectivity Prediction via Convolutional Neural Networks Based on geological Big Data

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Journal of Earth Science 2021年第2期32卷 327-347页

作者： Shi Li Jianping Chen Chang Liu Yang Wang School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China land Resources Information Development and Research Key Laboratory of Beijing Beijing 100083China Haikou Marine geological survey center China Geological SurveyHaikou 570100China

Today’s era of big data is witnessing a gradual increase in the amount of data,more correlations between data,as well as growth in their spatial *** linear statistical models applied to mineral prospectivity mapping(MPM)perform poorly because of the random and nonlinear nature of metallogenic *** overcome this performance degradation,deep learning models have been introduced in 3 D *** this study,taking the Huayuan sedimentary Mn deposit in Hunan Province as an example,we construct a 3 D digital model of this deposit based on the prospectivity model of the study *** this approach,3 D predictor layers are converted from the conceptual model and employed in a 3 D convolutional neural network(3 D CNN).The characteristics of the spatial distribution are extracted by the 3 D ***,we divide the 22 extracted ore-controlling variables into six groups for contrast experiments based on various combinations and further apply the 3 D CNN model and weight of evidence(WofE)method on each *** predictive model is trained on the basis of the coupling correlation between the spatial distributions of the variables and the underground occurrence space of the Mn orebodies,and the correlation between different ore-controlling *** analysis of 12 factors indicates that the 3 D CNN model performs well in the 3 D MPM,achieving a promising accuracy of up to 100%and a loss value below 0.001.A comparison shows that the 3 D CNN model outperforms the WofE model in terms of predictive evaluation indexes,namely the success rate and ore-controlling *** particular,the 1–12 ore-controlling factors selected in experiment 5 provide a significantly better prediction effect than the other ***,we conclude that the Mn deposit in the study area is not only related to the stratum and interlaminar anomalous bodies but also to the spatial distribution of the *** experimental results confirm that the proposed 3 D CNN is prom

关键词： big data mineral prospectivity mapping 3D geological modeling 3D CNN Huayuan Mn deposit

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Volcanic Facies and Their Reservoirs Characteristics in Eastern china Basins

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Journal of Earth Science 2013年第6期24卷 935-946页

作者：金春爽潘雯丽乔德武 Oil & Gas survey China Geological Survey Research Institute of Petroleum Exploration & Development PetroChina Strategic Research center of Oil & Gas Resources Ministry of Land & Resources

In these years, with more and more volcanic oil and gas fields being discovered and de- veloped, the volcanic rocks reveal a great petroleum potential in the eastern basins of china. There are five volcanic facies identified in the study area, which include volcanic conduit facies, explosive facies, effusive facies, extrusive facies, and volcanogenic sedimentary facies. The subaerial eruption usually happened in Mesozoic and Paleocene, and subaquatic eruption in Eocene. The upper subfacies and top autoclastic brecciation of effusive facies of subaquatic volcanic rocks and pyroclastic flow subfacies of explosive facies of subaerial volcanic rocks are the most favorable volcanic reservoirs. The intermittent belt formed between two times of volcanic eruptions is most effective for reservoirs both in subaquatic and subaerial volcanic rocks. Their main porosity types are interclast porosity, interflow laminar po- rosity, vesicular and gas pipes porosity, intercrystalline sieve of moldic porosity, secondary dissolution porosity, and tectonic fracture. Developed between pre-emplacement stage and final cooling, the pri- mary porosity may lead to high porosity and permeability, and the secondary porosity usually devel- oped upon them. The porosity of volcanic rocks was less influenced by the compaction and the burial depth.

关键词： volcanic facies volcanic reservoir porosity eastern china.

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