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Assessing the Impact of Industrial Zones on the Environmental Pollution in Hai Phong’s Coastal Areas, Vietnam
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作者 Pham Thi Song Thu Doan Quang Tri 《Journal of Geoscience and Environment Protection》 2023年第7期11-29,共19页
Pollution in the coastal areas negatively affects biochemical indicators of seawater, human health and marine organisms. Hai Phong is a coastal city of Vietnam with the development of socio-economic activities, repres... Pollution in the coastal areas negatively affects biochemical indicators of seawater, human health and marine organisms. Hai Phong is a coastal city of Vietnam with the development of socio-economic activities, representing through an increasing number of industrial zones. This study is to evaluate the pollution of large industrial zones in Hai Phong city using numerical models. The numerical simulation (MIKE 21 SW, FM, ECO Lab) models were applied to simulate the wave propagation, hydraulic regime, water quality in coastal Hai Phong area. The MIKE 21 ECO Lab model was used to evaluate sources of waste from the large coastal industrial zones to some aquaculture zones. The calibration and validation results of wave propagation and the hydrodynamic models were resonably good, with Nash coefficient ranging from 0.65 to 0.90 and a percent bias (PBIAS) from 5.6% to 9.4%. The simulation results of water quality and concentration of pollutants (DO, BOD<sub>5</sub>, COD, TSS, Fe, and Coliform) in 2023 at the aquaculture locations show that the BOD<sub>5</sub>, COD, and TSS concentrations were higher than the allowable limits stated in the national technical regulation on surface water quality (QCVN 08:2023/BTNMT) and lower than the allowable limits stated in the national technical regulation on marine water quality (QCVN 10:2023/BTNMT). The outcomes of this study will provide more information to support managers to come up with a better socio-economic development plan for Hai Phong city to achieve sustainable development. 展开更多
关键词 Coastal areas Water Quality MIKE 21 Industrial zones Costal Pollution
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Characteristics and origin of abnormally high porosity zones in buried Paleogene clastic reservoirs in the Shengtuo area, Dongying Sag, East China 被引量:19
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作者 Cao Yingchang Yuan Guanghui +5 位作者 Li Xiaoyan Wang Yanzhong Xi Kelai Wang Xiaoming Jia Zhenzhen Yang Tian 《Petroleum Science》 SCIE CAS CSCD 2014年第3期346-362,共17页
There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within ... There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within the Shengtuo area of the Dongying Sag. Here the porosity of reservoirs buried deeper than 4,000 m can still be greater than 20%. Investigation of these three abnormally high porosity (AHP) zones in the 3rd to 4th member of the Paleogene Shahejie Formation in the Shengtuo area was carried out with utilization of core observation, thin section identification, SEM observation, image analysis, core physical property testing and other technical methods. The results show that, the AHP zones in 2,800-3,200 m and 3,250-3,700 m are visible pores primary AHP zones dominated by significant primary intergranular pores (more than 50% of the total porosity), while secondary pores and micropores in authigenic clays may develop in some reservoirs. AHP reservoirs in the AHP zone of 3,900-4,400 m are dominated by micropores in matrix, visible pores are mainly grain dissolution pores but with low absolute content (〈 1%), so this zone belongs to the micropores primary AHP zone. The genesis of the three AHP zones was studied to distinguish between porosity enhancement and porosity preservation. Our research shows that, in deeply buried clastic reservoirs in the Shengtuo area, mineral dissolution occurred in a relatively closed diagenetic system with high temperature and high salinity. Reservoir rocks underwent extensive feldspar dissolution, while detrital carbonate grains and carbonate cements show no evidence of extensive dissolution. Although significant feldspar dissolution pores developed, feldspar dissolution enhanced porosity only a little due to the precipitation of almost isovolumetric dissolution products in the nearby primary intergranular pores in forms of authigenic clays and quartz cements. Net enhanced porosity originating from feldspar dissolution is generally less than 0.25%. Thus, the subsurface dissolution has little impact on the mid-deep buried high porosity reservoirs. Reservoirs in braided channels of middle fans in sublacustrine fans and reservoirs in the middle-front of fan bodies of nearshore subaqueous fans provide the basis for the development of AHP zones. The shallow development of fluid overpressure and early hydrocarbon emplacement have effectively retarded compaction and carbonate cementation, so that the high porosity in the superficial layers is preserved in the mid-deep layers. These are the main controlling factors in the development of AHP zones. 展开更多
关键词 Dongying Sag Shengmo area abnormally high porosity zone pores GENESIS
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Changes in the network of tourist trails in the border zones of the Czech Republic after entering the Schengen area 被引量:3
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作者 Krzysztof KOLODZIEJCZYK 《Journal of Mountain Science》 SCIE CSCD 2020年第4期949-972,共24页
Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it... Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it was decided to look at changes in the offer of tourist trails(hiking and cycling) along the entire border of the Czech Republic after the extension of the Schengen area(within this area, crossing the border is possible anywhere, and not only at official border crossings). It should be emphasized here that the borders of the Czech Republic over most of their length run through mountainous areas and, apart from political factors, natural features should have a major impact on the development of tourist routes. In order to determine the coherence of the current network of trails on both sides of the Czech Republic state border, modern tourist maps have been analyzed, determining the number of places where it is possible to cross the state border with the help of a marked tourist trail. Based on that, two indicators were introduced to determine the degree of openness with all neighboring countries as regards the opportunity to cross on a tourist trail. Changes in the historical situation, a comparison of the accessibility of the border area before entering the Schengen area and 2019, were analyzed for two study areas using archival maps. Over a decade after the extension of the Schengen area, the number of places where tourist trails of neighboring countries approach the border has clearly increased. Crossing is more often made possible using hiking trails than cycling routes(trails of the first type cross the border every 7.91 km, while the latter every 13.3 km), but considering the speed of movement, it can be assessed that the openness for cyclists is higher than for hikers. Moreover, in many places there is still significant potential for further integration of tourist trail networks as trails created in one country often do not have a continuation on the other side of the border. 展开更多
关键词 Tourist trails Schengen area Border zone MOUNTAINS Czech Republic
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Migration and speciation transformation mechanisms of mercury in undercurrent zones of the Tongguan gold mining area, Shaanxi Loess Plateau and impact on the environment 被引量:4
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作者 Rui-ping Liu You-ning Xu +2 位作者 Hui-chao Rui El-Wardany RM Ying Dong 《China Geology》 2021年第2期311-328,共18页
In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment,the field in-situ infi... In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment,the field in-situ infiltration test and laboratory test were carried out in three typical sections of river-side loess,alluvial and proluvial strata in Tongguan gold mining area of Shaanxi Province,and the following results were obtained:(1)The source of Hg in subsurface flow zone is mainly caused by mineral processing activities;(2)the subsurface flow zone in the study area is in alkaline environment,and the residual state,iron and manganese oxidation state,strong organic state and humic acid state of mercury in loess are equally divided in dry and oxidizing environment;mercury in river alluvial or diluvial strata is mainly concentrated in silt,tailings and clayey silt soil layer,and mercury has certain stability,and the form of mercury in loess is easier to transform than the other two media;(3)under the flooding condition,most of mercury is trapped in the silt layer in the undercurrent zone where the sand and silt layers alternate with each other and the river water and groundwater are disjointed,and the migration capacity of mercury is far less than that of loess layer and alluvial layer with close hydraulic connection;(4)infiltration at the flood level accelerates the migration of pollutants to the ground;(5)the soil in the undercurrent zone is overloaded and has seriously exceeded the standard.Although the groundwater monitoring results are safe this time,relevant enterprises or departments should continue to pay attention to improving the gold extraction process,especially vigorously rectify the small workshops for illegal gold extraction and the substandard discharge of the three wastes,and intensify efforts to solve the geological environmental problems of mines left over from history.At present,the occurrence form of mercury in the undercurrent zone is relatively stable,but the water and soil layers have been polluted.The risk of disjointed groundwater pollution can not be ignored while giving priority to the treatment of loess and river alluvial landform areas with close hydraulic links.The research results will provide a scientific basis for water conservancy departments to groundwater prevention and control in water-deficient areas of the Loess Plateau. 展开更多
关键词 Mercury speciation Hyporheic zones Constant surface water level Flood level Surface-groundwater Hydraulic connection Tongguan gold mining areas Loess Plateau Shannxi Province
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Feasibility of Protection Zones for Water Resources in Arid Areas: Case Study;Duyuk Nueimah Shosa Springs, Jericho, Palestine
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作者 Marwan Ghanem Mahmoud Hammad 《Journal of Environmental Protection》 2015年第2期110-117,共8页
Urbanization and different human-economic activities put increasing pressure on the ground water quality, which is considered as the main drinking water resources in Palestine. Protecting the spring water resources in... Urbanization and different human-economic activities put increasing pressure on the ground water quality, which is considered as the main drinking water resources in Palestine. Protecting the spring water resources in Palestine is one major issue for the continuity of the availability of the water resources. An economic feasibility study was conducted for the Nuewimah-Shosha-Dyuk spring system in order to assess the economical factor for the induced methodology of the protection zones. The spring system has multiple users from different sectors (i.e., domestic, agriculture, commercial and public use) and multi-year cost benefit analysis technique used to show the feasibility of water protection zones on the long run. The study shows that even in arid areas in Palestine, small quantities are derived from springs-implementation of water protection zones is still feasible;the results of this study emphasize on importance and feasibility of water resources protection zones. 展开更多
关键词 Water PROTECTION zones COST BENEFIT Analysis PROTECTION zones Guidelines Nueimah Spring System Jericho area
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Can We Manage Coastal Area? Will We?——The Institutional Change of the Coastal Area Management of Taiwan
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作者 Yuh-fen Kao 《Management Studies》 2024年第1期21-32,共12页
The Coastal Zone Management Act was finally promulgated in 2015,while Ministry of the Interior was asked to draft a coastal management act in 1991 by Executive Yuan.It was until the government’s lifting of martial la... The Coastal Zone Management Act was finally promulgated in 2015,while Ministry of the Interior was asked to draft a coastal management act in 1991 by Executive Yuan.It was until the government’s lifting of martial law in 1987,vigorous activities started prevailing on coastal areas.And relevant legal documents were on sea reclamation for development in the 1980’s by Council of Agriculture.The approval of“Taiwan Coastal Area Natural Environment Protection Plan”showed an era of environmental protection in 1980s.However,it was surely not market driven,similar to land development,but some efforts by the administration systems.Through all the years,the efforts were put on drafting plans and these efforts were not quite sounding.The coastal disasters and further climate change caught the attention of relevant NGOs,scholars,politicians,and the society.At the critical juncture the government was made to react to outside demands.And then the Coastal Zone Management Act was passed by Legislative Yuan,establishing an integrated coastal management system in Taiwan.As such,it is proposed to look into this long process of the attempt with the concept of institutional change in order to understand this coastal environmental preservation and protection issue in a broader scope. 展开更多
关键词 Integrated Coastal zone Management(ICZM) institutional change new institutionalism coastal area
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Landslide Vulnerable Zones Based on Engineering Geological Assessment, Case Study: Wonotopo Area, Gebang District, Purworejo Regency, Central Java, Indonesia
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作者 Sari Bahagiarti Kusumayudha Delvianus Kaesmetan Heru Sigit Purwanto 《Journal of Geological Resource and Engineering》 2019年第3期93-104,共12页
Landslide is one of the geological disasters that frequently occur on the natural slopes, often threatening community of the adjacent area. Therefore, it is necessary to hold engineering geological research and assess... Landslide is one of the geological disasters that frequently occur on the natural slopes, often threatening community of the adjacent area. Therefore, it is necessary to hold engineering geological research and assessment in disaster-prone regions such as Gebang district of Purworejo Regency, Central Java Province, Indonesia. This research was conducted to determine and analyze the type of mass movements, factor of safety, potential landslide areas, vulnerable zonation, factors influencing the stability of the slope, and to propose the disaster mitigation recommendation. The methods applied in the research are surface geological mapping, physical soil-rock properties testing, engineering geological assessment and analysis, and Regulation of Minister of Public Works of Republic of Indonesia number 22/PRT/M/2007, on Guidelines to Spatial Planning for Landslide Disaster Areas. To create information on the threats of land movements, a map on landslide potential zonation is developed by considering seven important aspects including: slope inclination, soil conditions, slope constituents, rainfall, slope water condition, seismicity, and vegetation or land use. The results show that, the landslide prone zone of the study area can be divided into 2 types, namely type B and type C. Landslide potential zone of type B involves high level of vulnerability and moderate level of vulnerability. Meanwhile, the landslide potential zone of type C consists of high level of vulnerability and low level of vulnerability. 展开更多
关键词 LANDSLIDE VULNERABLE zone ENGINEERING GEOLOGICAL ASSESSMENT mitigation Wonotopo area.
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Zone,District,Region和Area的使用与翻译
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作者 杨文芳 《英语研究》 2013年第2期48-51,共4页
Zone,district,region和area都有"地区、区域"的含义,但在使用和翻译时,它们有各自不同的语境和特点,使用大量通俗易懂的例句来说明"zone,district,region和area"在汉语中的正确使用和翻译。
关键词 zone DISTRICT REGION area 翻译
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Hydrocarbon migration and accumulation along the fault intersection zone-a case study on the reef-flat systems of the No.1 slope break zone in the Tazhong area, Tarim Basin 被引量:14
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作者 Xiang Caifu Pang Xiongqi +4 位作者 Yang Wenjing Wang Jianzhong LiQiming Liu Luofu Li Yanqun 《Petroleum Science》 SCIE CAS CSCD 2010年第2期211-225,共15页
Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest Chin... Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality (2-3 orders of magnitude at the intersection zone) and the formation mechanisms of the fault intersection zone. Differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized. 展开更多
关键词 Geologic chromatographic effect fault intersection zone differential hydrocarbon migration and accumulation superimposed basin Tazhong area Tarim Basin
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Instability identification on large scale underground mined-out area in the metal mine based on the improved FRBFNN 被引量:4
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作者 Luo Zhouquan Zuo Hongyan +1 位作者 Jia Nan Wang Yiwei 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期821-826,共6页
To identify the instability on large scale underground mined-out area in the metal mine effectively,the parameters of radial basis function were determined through clustering method and the improved fuzzy radial basis... To identify the instability on large scale underground mined-out area in the metal mine effectively,the parameters of radial basis function were determined through clustering method and the improved fuzzy radial basis function neural network(FRBFNN)model of instability identification model about large scale underground mined-out area in the metal mine was built.The improved FRBFNN model was trained and tested.The results show that the improved FRBFNN model has high training accuracy and generalization ability.Parameters such as pillar area ratio,filling level and the value of rock quality designation have strong influence on instability of large scale underground mined-out area.Correctness of analysis about the improved FRBFNN model was proved by the practical application results about instability discrimination of surrounding rock in large-scale underground mined-out area of a metal mine in south China. 展开更多
关键词 Metal mine Fuzzy theory mined-out area RBF neural network DISCRIMINATION
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Quantitative analysis of biotechnical reinforcement for a steep slope consisting of composite coal-gangue-soil medium adjacent to a mined-out area 被引量:3
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作者 Xingping Lai Mowen Xie +1 位作者 Fenhua Ren Meifeng Cai 《Journal of University of Science and Technology Beijing》 CSCD 2005年第6期489-494,共6页
The engineering and geological characteristics of a steep slope consisting of coal gangue, rock and soil medium in Huating coal mine have been comprehensively investigated. Owing to humid weather, heavy rainfall, vege... The engineering and geological characteristics of a steep slope consisting of coal gangue, rock and soil medium in Huating coal mine have been comprehensively investigated. Owing to humid weather, heavy rainfall, vegetation and porous characteristics of the soil and rock mass, the steep slope will be destabilized and induce mud-rock flow or derive hazard easily. Firstly, based on the classical slope reinforcement theory, some regularity between the shear and displacement in the destabilized zone of the slope with or without root strength contribution is presented. Then, based on the experimental and statistical analysis of root strength, hydrological characteristics and stability status, etc., some possible biotechnical techniques for reinforcement of the steep slope have been suggested. These methods are important for quantitative analysis of destabilization of the slope and design of the biotechnical reinforcement. 展开更多
关键词 mined-out area coal-gangue-soil composite medium steep slope root-soil effect biotechnical reinforcement
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Time function of surface subsidence based on Harris model in mined-out area 被引量:7
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作者 Liu Xinrong Wang Junbao +2 位作者 Guo Jianqiang Yuan Hong Li Peng 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期251-254,共4页
The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve mod... The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve model in consideration of the shortage of current surface subsidence time functions. By analyzing the characteristics of the new time function, we found that it could meet the dynamic process, the velocity change process and the acceleration change process during surface subsidence. Then its rationality had been verified through project cases. The results show that the proposed time function model can give a good reflection of the regularity of surface subsidence in mined-out area and can accurately predict surface subsidence. And the prediction data of the model are a little greater than measured data on condition of proper measured data quantity, which is safety in the engineering. This model provides a new method for the analysis of surface subsidence in mined-out area and reference for future prediction, and it is valuable to engineering application. 展开更多
关键词 mined-out area Surface subsidence Time function Harris model Prediction
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Structural patterns of fault damage zones in carbonate rocks and their influences on petroleum accumulation in Tazhong Paleo-uplift, Tarim Basin, NW China 被引量:4
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作者 NENG Yuan YANG Haijun DENG Xingliang 《Petroleum Exploration and Development》 2018年第1期43-54,共12页
Based on the outcrop survey,3D seismic data interpretation,drilling data analysis,the structural patterns and distribution of fault damage zones in carbonate strata of Tazhong Paleo-uplift were established to reveal t... Based on the outcrop survey,3D seismic data interpretation,drilling data analysis,the structural patterns and distribution of fault damage zones in carbonate strata of Tazhong Paleo-uplift were established to reveal the oil and gas enrichment law in the fault damage zones.The following findings were reached:(1)Through the filed survey,the fault damage zone system consists of fault core,damage zone with branch fault and fracture network.Affected by the active nature of the major faults,the fault damage zones differ in planar pattern and scale along the major faults.(2)3D seismic profiles reveal that there are three types of fault damage zones in carbonate strata in Tazhong paleo-uplift,strike-slip fault damage zones,thrust fault damage zones and superimposed fault damage zones.Featuring3 flowers and 3 root belts in vertical,the strike-slip fault damage zone can be subdivided into linear type,oblique type,feather type and horsetail type in plane.Thrust fault damage zones can be further divided into fault anticline type,anticline type and slope type.As the superimposition result of the above two kinds of fault damage zones,superimposed fault damage zones appear in three patterns,intersect type,encompassment type and penetrating type.(3)Cores from wells and geochemical data show oil and gas may migrate along the major fault and laterally.The feather type in strike-slip fault system,fault anticline type in thrust fault damage zone and intersect type in superimposed fault damage zone are possible sites for high production and efficiency wells. 展开更多
关键词 TAZHONG PALEO-UPLIFT CARBONATE STRATA fault damage zone structural pattern high production well area
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Earthquake-controlling Processes of Detachment Zones in Eastern North China 被引量:1
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作者 SUNAiqun NIUShuyin +2 位作者 SHAOJi'an HOUQuanlin ZHANGJianzhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期283-290,共8页
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersectio... The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materials were detached outward. When the detached middle and lower crust come to the boundary of fault basins in the upper crust, they will be obstructed by the orogenic zone and the detachment will go slower. The shearing between them will cause the stress to accumulate and release alternatively, so that earthquakes occurred frequently in the areas of sub-mantle plume and its surroundings. 展开更多
关键词 sub-mantle plume detachment belt earthquake-controlling structure low-velocity and high-conductivity zones north China basin-and range area
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Mapping favorable groundwater potential recharge zones using a GIS-based analytical hierarchical process and probability frequency ratio model:A case study from an agro-urban region of Pakistan 被引量:3
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作者 Arfan Arshad Zhijie Zhang +1 位作者 Wanchang Zhang Adil Dilawar 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第5期1805-1819,共15页
In Punjab(Pakistan),the increasing population and expansion of land use for agriculture have severely exploited the regional groundwater resources.Intensive pumping has resulted in a rapid decline in the level of the ... In Punjab(Pakistan),the increasing population and expansion of land use for agriculture have severely exploited the regional groundwater resources.Intensive pumping has resulted in a rapid decline in the level of the water table as well as its quality.Better management practices and artificial recharge are needed for the development of sustainable groundwater resources.This study proposes a methodology to delineate favorable groundwater potential recharge zones(FPRI)by integrating maps of groundwater potential recharge index(PRI)with the DRASTIC-based groundwater vulnerability index(VI).In order to evaluate both indexes,different thematic layers corresponding to each index were overlaid in ArcGIS.In the overlay analysis,the weights(for various thematic layers)and rating values(for sub-classes)were allocated based on a review of published literature.Both were then normalized and modified using the analytical hierarchical process(AHP)and a frequency ratio model respectively.After evaluating PRI and FPRI,these maps were validated using the area under the curve(AUC)method.The PRI map indicates that 53%of the area assessed exists in very low to low recharge zones,22%in moderate,and 25%in high to excellent potential recharge zones.The VI map indicates that 38%of the area assessed exists in very low to low vulnerability,33%in moderate,and 29%in high to very high vulnerability zones.The FPRI map shows that the central region of Punjab is moderately-to-highly favorable for recharge due to its low vulnerability and high recharge potential.During the validation process,it was found that the AUC estimated with modified weights and rating values was 79%and 67%,for PRI and VI indexes,respectively.The AUC was less when evaluated using original weights and rating values taken from published literature.Maps of favorable groundwater potential recharge zones are helpful for planning and implementation of wells and hydraulic structures in this region. 展开更多
关键词 Weightage overlay Analytical hierarchical process(AHP)analysis Frequency ratio(FR) VULNERABILITY Groundwater recharge zones area under curve(AUC)
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THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
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作者 朱震达 刘恕 杨有林 《Chinese Geographical Science》 SCIE CSCD 1991年第1期32-43,共12页
The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified ... The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood,the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone,the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing 展开更多
关键词 desertified lands the transitional zone BETWEEN the dry-larming area and the GRAZING area remanagement NORTH China.
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Ecological-breaking zone originates and its ecosystem reconstruction in aridarea
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作者 Huang Peiyou Lu Zili(Biology Department of Xinjiang University,Urumqi 830046,China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第2期203-211,共9页
In the process of arid land exploitation, the landscape of desert is divided into three types. Oasis is rising,the area of uneffected area keeps its original state,the serious degenerated area where is only limited be... In the process of arid land exploitation, the landscape of desert is divided into three types. Oasis is rising,the area of uneffected area keeps its original state,the serious degenerated area where is only limited between oasis and desert, but not overall. Its relationship with the neighbor region, the zone of ecological-breaking region or ecological rift valley is not successive. . Its ecological effect endangered the arid land overall. Rehabilitating vegetation is the basic measure for abatement. The authors proposed a new tactics that based on the properties of vegetation. Depending on the local water sources and partly regulating the composition of environmental factor to satisfy the requirement of desert community, the rehabilitate vegetation should be realized. 展开更多
关键词 arid area ecological-breaking zone ecosystems reconstruction.
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A novel strategy of smart manipulation by micro-scale oscillatory networks of the reactionary zones for enhanced extreme thrust control of the next-generation solid propulsion systems
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作者 Alexander N.Lukin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期635-642,共8页
The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano... The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano-scale combustion mechanisms is essential to the development and further improvement of the next-generation technologies for extreme control of the solid propellant thrust. Both experiments and theory confirm that the micro-and nano-scale oscillatory networks excitation in the solid propellants reactionary zones is a rather universal phenomenon. In accordance with our concept,the micro-and nano-scale structures form both the fractal and self-organized wave patterns in the solid propellants reactionary zones. Control by the shape, the sizes and spacial orientation of the wave patterns allows manipulate by the energy exchange and release in the reactionary zones. A novel strategy for enhanced extreme thrust control in solid propulsion systems are based on manipulation by selforganization of the micro-and nano-scale oscillatory networks and self-organized patterns formation in the reactionary zones with use of the system of acoustic waves and electro-magnetic fields, generated by special kind of ring-shaped electric discharges along with resonance laser radiation. Application of special kind of the ring-shaped electric discharges demands the minimum expenses of energy and opens prospects for almost inertia-free control by combustion processes. Nano-sized additives will enhance self-organizing and self-synchronization of the micro-and nano-scale oscillatory networks on the nanometer scale. Suggested novel strategy opens the door for completely new ways for enhanced extreme thrust control of the solid propulsion systems. 展开更多
关键词 Solid propulsion systems EXTREME thrust control Reactionary zones MICRO-SCALE OSCILLATORY NETWORKS SELF-ORGANIZED wave patterns Energy-releasing areas
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Bidding Scheme Design of Central Recreational Area for Xiaogan Linkong Economic Zone
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作者 WANG Ai'guo SUN Ti 《Journal of Landscape Research》 2016年第5期48-52,共5页
This paper elaborated the bidding scheme design of the Central Recreational Area in Linkong Economic Zone from the perspectives of site analysis, determination of properties, design theme and principle, scheme layout ... This paper elaborated the bidding scheme design of the Central Recreational Area in Linkong Economic Zone from the perspectives of site analysis, determination of properties, design theme and principle, scheme layout and conception, in order to explore the potential enlightenments of the scheme design process, and disclose significance of site analysis and its close relationship with the scheme design. 展开更多
关键词 Linkong Economic zone Central Recreational area Bidding scheme Water show Phoenix dancing
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A multi-scale 3-D crust velocity model in the Hefei-Chao Lake area around the southern segment of Tanlu Fault Zone
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作者 Lingli Li Huajian Yao +4 位作者 Song Luo Junhui Li Xiaoli Wang Hongyu Ni Ziwen Bao 《Earthquake Science》 2021年第4期344-357,共14页
Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the ... Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the main geological units of Hefei Basin,with thick sediments and the Chao Lake depression.Several major concealed faults of the southern NNE-trending Tanlu Fault Zone cross this area.To further explore the underground distribution characteristics of the faults and their tectonic evolutionary relationship with adjacent tectonic units,this study used ambient noise data recorded by a seismic array deployed in Hefei City and Chao Lake,constructing a 3-D velocity model at the depth of 1–8 km.Then a multi-scale high-resolution 3-D velocity model of this area was constructed by this new upper crustal velocity model with the previous middle and lower crustal model.The new model reveals that a high-velocity belt is highly consistent with the strike of the Tanlu Fault Zone,and a low-velocity sedimentary characteristic is consistent with the Hefei Basin and Chao Lake depression.The distribution morphology of high and low velocity bodies shows that the sedimentary pattern of Hefei-Chao Lake area is closely related to the tectonic evolution of the Tanlu Fault Zone since the Mesozoic.This study also identifies multiple low-velocity anomalies in the southeastern Hefei City.We speculate that strong ground motion during the 2009 Feidong earthquake(magnitude of 3.5)was related to amplification by the thick sediments in the Hefei Basin.We also discuss further applications of multi-scale high-resolution models of the shallow layer to strong ground motion simulations in cities and for earthquake disaster assessments. 展开更多
关键词 Tanlu Fault zone Hefei-Chao Lake area CRUST multi-scale velocity model
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