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Quantitative characterization of vertical zonation of Mesozoic granite weathering reservoirs in the coastal area of eastern Fujian Province,China
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作者 Jing-Song Hu Yi-Ming Jiang +3 位作者 Hua-Feng Tang Wen-Rui Ma Peng Tao Ning-Yuan Sun 《Petroleum Science》 SCIE EI CSCD 2023年第5期2664-2682,共19页
Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characteriz... Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characterization of granite weathering crust reservoir and provide the basis for oil exploration of granite weathering crust buried hill reservoir,in this paper,the vertical zonation of granite weathering crust reservoir is quantitatively divided by testing and analyzing the uniaxial compressive strength(UCS),magnetic susceptibility(MS),permeability,and chemical index of alteration(CIA)of the Mesozoic granite weathering crust in the coastal area of eastern Fujian.The results show that the granite weathering crust reservoir can be divided into four zones vertically:a soil zone(SZ),weathered and dissolved zone(WDZ),fracture zone(FZ),and bedrock zone(BZ).A cataclastic area is developed in the FZ and BZ,in which structural fractures are well-developed,the fracture surface density is usually greater than 200 m/m^(2),and the contribution to the fractures in the rock mass is up to about 50%,making this the sweet spot of the reservoir.In the SZ,the rocks are loose,and the pores are well-developed.The UCS is less than 10 MPa,and the average rate of change of the UCS(Δ_(σ))is 0.90.The average permeability is 2823.00 mD,and the average rate of change of the permeability(Δ_(κ))is 5.13.The average CIA is 74.9%.The average clay mineral content is 7%.The rocks in the WDZ have been significantly weathered by physical and chemical processes,and the weathering fractures and dissolution pores are well-developed.The average UCS is 18.2 MPa,and the averageΔ_(σ)is 0.70.The average permeability is 143.80 mD,and averageΔ_(κ)is 4.17.The average CIA is 65.3%.The average clay mineral content is 4%.Under the influence of tectonic movement and physical weathering,the rocks in the FZ have developed structural fractures and a few weathered fractures.The average UCS is 57.9 MPa,and the averageΔ_(σ)is 0.18.The average permeability is 5.50 mD,and the averageΔ_(κ)is 2.55.The average CIA is 61.6%.The average clay mineral content is 2%.In the BZ,the rocks are intact and hard.The average UCS is 69.9 MPa,and the average Ds is 0.13.The average permeability is 1.46 mD,and the averageΔ_(κ)is 1.43.The average CIA is 57.8%.The average clay mineral content is less than 1%.The multi-parameter combination of the UCS,Δ_(σ),permeability,Δ_(κ),CIA,and clay mineral content achieved good results in the division of the zones of the weathering crust.The UCS increases gradually from top to bottom,while Ds,permeability,Δ_(κ),CIA,and clay mineral content all decrease gradually.In addition,based on the petrophysical parameters of the rocks,including the density,resistivity,and acoustic velocity,a good division effect was also achieved,which can provide a basis for the vertical zonation of the granite buried-hill weathering crust reservoir. 展开更多
关键词 Granite weathering crust Vertical zonation of reservoir Quantitative characterization Eastern Fujian Mesozoic granite
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基于MAXENT和ZONATION的加拿大一枝黄花入侵重点监控区确定 被引量:35
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作者 李丽鹤 刘会玉 +2 位作者 林振山 贾俊鹤 刘翔 《生态学报》 CAS CSCD 北大核心 2017年第9期3124-3132,共9页
外来入侵植物对本地生态系统及其生物多样性构成严重的威胁,要有效地控制外来植物入侵,首先应该明确植物入侵的高度风险区.以加拿大一枝黄花(Solidago canadensis)为对象,以其广泛发生的安徽、江苏、浙江和上海华东3省1市为研究区域,综... 外来入侵植物对本地生态系统及其生物多样性构成严重的威胁,要有效地控制外来植物入侵,首先应该明确植物入侵的高度风险区.以加拿大一枝黄花(Solidago canadensis)为对象,以其广泛发生的安徽、江苏、浙江和上海华东3省1市为研究区域,综合考虑了土地利用变化、人类活动干扰、土壤性质、气候和地形等影响因子,采用MAXENT模型预测其潜在分布及其对主要影响因子的响应,并结合空间优化软件ZONATION识别出需要重点布控的入侵风险区。结果表明:1)影响加拿大一枝黄花分布的主要环境因子及其百分比贡献率分别为:距主要道路距离(29.4%)、土地利用变化(16.9%)、降水的季节性变异(15.9%)、人口密度(9.5%)与最干季均温(6.2%)。2)从影响因子的响应曲线分析得出,加拿大一枝黄花的发生概率随着距主要道路距离的增大而迅速减小;在耕地转化成的城乡居民点及工矿用地、水域转化成的草地、城乡居民点及工矿用地转化成的林地、草地与城乡居民点及工矿用地相互转换频繁的区域和城乡居民点及工矿用地保持不变的区域,其发生概率明显较高;其发生概率随着降水季节性变异的增大而快速减小至0.4,之后缓慢减小;随着人口密度的增大,其发生概率起初急剧升高,人口密度超过4千人/km^2后又缓慢地小幅下降;随着最干季均温的增大,其发生概率逐渐减小,在2.4℃附近达最小,之后逐渐增大。3)加拿大一枝黄花的入侵风险区面积为130433 km^2。其中,一级风险区主要分布在太湖流域、沿杭州湾地区、浙江沿海以及内陆地势较低的耕地及居民点区域;二级风险区主要分布在一级风险区的外缘,尤其是江苏南部的长江沿岸地区。三级风险区则广泛分布在江苏的南部和东部,安徽的中东部,浙江的北部和东部。 展开更多
关键词 加拿大一枝黄花 MAXENT 风险预测 响应 zonation
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基于ZONATION的岷山山系多物种保护规划 被引量:11
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作者 肖静 崔莉 李俊清 《生态学报》 CAS CSCD 北大核心 2016年第2期420-429,共10页
空间布局不尽合理是我国的自然保护区发展面临的问题之一,优化现有的自然保护区体系是在资源有限的情况下实现自然保护区的保护效益最大化的最佳途径。以岷山地区为主要研究区域,以25种珍稀濒危物种为主要研究对象,通过MAXENT与ZONATIO... 空间布局不尽合理是我国的自然保护区发展面临的问题之一,优化现有的自然保护区体系是在资源有限的情况下实现自然保护区的保护效益最大化的最佳途径。以岷山地区为主要研究区域,以25种珍稀濒危物种为主要研究对象,通过MAXENT与ZONATION模型模拟,鉴别出岷山地区珍稀濒危物种保护优先区,并提出了自然保护区空间选址的优化方案。研究结果表明,(1)在物种出现点记录较少的情况下,MAXENT模型依然能够比较准确地预测出物种的分布状况;(2)目前建立的保护区对25个物种的平均保护比例为51.8%;(3)通过ZONATION鉴定的优先区总面积为19958.7 km^2,岷山地区现有的29个自然保护区只保护了目标优先区的47.1%,九寨沟中部与南部,平武北部,平武与北川的交界处,北川西北部等地都存在保护空缺。建议在保护空缺的6个地方新建或扩建自然保护区,并在规划时考虑这些区域内部的优先次序。新提出的保护体系能将物种栖息地的保护比例提高至77.9%。研究结果对于岷山及全国其他生物多样性保护关键地区保护体系的规划都具有重要的借鉴意义。 展开更多
关键词 自然保护区 规划 优先区 zonation 岷山
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对于有序聚类程序包ZONATION中几个算法的分析与应用实例 被引量:1
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作者 邢雪 童国榜 林锦璇 《石油实验地质》 CAS CSCD 北大核心 1991年第1期93-98,共6页
本文对有序聚类程序色ZONAION(“分带”)中所用的三种算法(其中两个算法各含两种度量指标)进行了介绍与剖析,并以天津Ⅰ24孔钴井中的孢粉序列分析为例对方法进行了验证。
关键词 有序聚类 程序色 岩芯 zonation
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Geochemical Characteristics and Zonation of Primary Halos of Pulang Porphyry Copper Deposit,Northwestern Yunnan Province,Southwestern China 被引量:11
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作者 陈永清 黄静宁 梁贞 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期371-377,共7页
The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large c... The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K2≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag*Zn)D/(Mo×W)D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth. 展开更多
关键词 Pulang porphyry copper deposit zonation of primary halo assessment of Cu potential at depth Tethys-Himalaya ore-forming domain southwestern China
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CIS-Based Mapping and Zonation of Landslide Hazards in Xiaojiang Valley of Southwestern China 被引量:7
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作者 MaZe-zhong HeYi-ping +3 位作者 XieHong CuiPeng ZhongDun-lun JamesS.Gardner 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1021-1028,共8页
Through the field survey, previous researches and interpretation of aerial photos, a landslide information database of Xiaojiang Valley, Yunnan Province was set up based on the remote sensing (RS) and geographic infor... Through the field survey, previous researches and interpretation of aerial photos, a landslide information database of Xiaojiang Valley, Yunnan Province was set up based on the remote sensing (RS) and geographic information system (GIS) technologies. In the paper, a quantitative model for the landslide hazard assessment and zoning was presented, in which the potential energy could be obtained on basis of thorough analysis of the potential sliding volume, distance and direction of the landslide body. Taking landslide potential energy as the index of the hazard severity zonation, the study area was divided into severe, heavy, medium and light hazard zones. 展开更多
关键词 LANDSLIDE hazard mapping zonation Xiao- jiang Valley southwestern China
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Torrent risk zonation in the Upstream Red River Basin based on GIS 被引量:5
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作者 TANG Chuan ZHU Jing 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期479-486,共8页
This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,00... This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,000 scale digital map, six factors including slope angle, rainstorm days, buffer of river channels, maximum runoff discharge of standard area, debris flow distribution density and flood disaster history were analyzed and superimposed to create the torrent risk evaluation map. Population density, farmland percentage, house property, and GDP as indexes accounting for torrent hazards were analyzed in terms of vulnerability mapping. Torrent risk zonation by means of GIS was overlaid on the two data layers of hazard and vulnerability. Then each grid unit with a resolution of 500 m- 500 m was divided into four categories of the risk: extremely high, high, moderate and low. Finally the same level risk was combined into a confirmed zone, which represents torrent risk of the study area. The risk evaluation result in the upper Red River Basin shows that the extremely high risk area of 13,150 km^2 takes up 17.9% of the total inundated area, the high risk area of 33,783 km^2 is 45.9%, the moderate risk area of 18,563 km^2 is 25.2% and the low risk area of 8115 km^2 is 11.0%. 展开更多
关键词 torrent risk zonation GIS the Upstream Red River Basin
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Liver zonation: Novel aspects of its regulation and its impact on homeostasis 被引量:3
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作者 Rolf Gebhardt Madlen Matz-Soja 《World Journal of Gastroenterology》 SCIE CAS 2014年第26期8491-8504,共14页
Liver zonation,the spatial separation of the immense spectrum of different metabolic pathways along the liver sinusoids,is fundamental for proper functioning of this organ.Recent progress in elucidating localization a... Liver zonation,the spatial separation of the immense spectrum of different metabolic pathways along the liver sinusoids,is fundamental for proper functioning of this organ.Recent progress in elucidating localization and interactions of different metabolic pathways by using"omics"techniques and novel approaches to couple them with refined spatial resolution and in characterizing novel master regulators of zonation by using transgenic mice has created the basis for a deeper understanding of core mechanisms of zonation and their impact on liver physiology,pathology and metabolic diseases.This review summarizes the fascinating technical achievements for investigating liver zonation and the elucidation of an emerging network of master regulators of zonation that keep the plethora of interrelated and sometimes opposing functions of the liver in balance with nutritional supply and specific requirements of the entire body.In addition,a brief overview is given on newly described zonated functions and novel details on how diverse the segmentation of metabolic zonation may be.From these facts and developments a few fundamental principles are inferred which seem to rule zonation of liver parenchyma.In addition,we identify important questions that still need to be answered as well as interesting fields of research such as the connection of zonation with circadian rhythm and gender dimorphism which need to be pushed further,in order to improve our understanding of metabolic zonation.Finally,an outlook is given on how disturbance of liver zonation and its regulation may impact on liver pathology and the development of metabolic diseases. 展开更多
关键词 HOMEOSTASIS LIVER METABOLIC zonation METABOLISM Mo
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Mineralogical Zonation of Wall-Rock Alteration in Jiaodong Gold Province, North China 被引量:3
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作者 Chen Guangyuan Sun Daisheng Shao Wei Li Shengrong Division of Genetic Mineralogy, China University of Geosciences, Beijing 100083 Fyfe S. William Department of Earth Sciences, University of Western Ontario, London, Ontario, Canada, N6A 5B7 Chen 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期20-24,共5页
Mineralogical zonation of wall rock alterations in Mesozoic granitoids is summarized from 18 gold deposits in Jiaodong gold province on the Asian mobile continental margin of the west circum Pacific rim. This paper ... Mineralogical zonation of wall rock alterations in Mesozoic granitoids is summarized from 18 gold deposits in Jiaodong gold province on the Asian mobile continental margin of the west circum Pacific rim. This paper deals with wall rock alterations developed around gold mineralizations of the quartz vein type in granitoids and the wall rock alteration type in granitoid basement contacts along Mesozoic fault zones trending mostly NNE SSW and NE SW. Five alteration zones are distinguished from host rock to ore zone, namely the chloritization and sericitization zone, the hematitization rutilization and microclinization zone, the quartz sericitization zone, the pyrite quartz sericitization zone and the pyrite silicification zone. The former two are outer zones marked by incomplete alteration of first mafic and then felsic minerals of the granitoids, while the later three are inner zones marked by complete alteration of both mafic and felsic minerals of the granitoids leading to retrogressive sericitization and progressive silicification with participation of ore elements. The whole process proceeds under dynamometamorphism with high fugacity of volatiles. Wall rock alteration is the intermediate link between unaltered host rock and ore mineralization both in time and space. Development of the alteration zonation and its mineral composition controls genetic type of mineralization, size and grade of the deposit and location of the ore zones. 展开更多
关键词 gold province wall rock alteration zonation mineralogy Jiaodong.
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Assessment and Risk Zonation of Landslides in Panxi Area Based on 3S Technology 被引量:3
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作者 ZHANG Baolei SONG Shujun +1 位作者 FENG Wenlan ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期793-800,共8页
Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce lan... Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce landslides such as the elevation, the slope, the vegetation cover, the lithology, the rainfall and so on are gained using GIS(geographical information system) techniques of spatial analysis. All the data obtained are managed through building landslide management system. At the same time, the system is made the platform to appraise the relationship between the distribution of landslides and the environmental factors. The results indicate: landslides take place relatively easily in the slope range between 10° and 25°; most landslides are in the mixed area of bush and grass with a coverage degree of from 20° to 65°; the distribution of landslides has a positive relationship with the distribution of annual rainfall. The risk degree of Panxi Area is zoned and mapped by the model of liner stack using GIS technique, and the result indicates: the place of high risk degree is the belt of Panzhihua-Miyi-Dechang-Mugu and southeast of Huili county and Huidong county,and area is about 512 707 hm^2. 展开更多
关键词 LANDSLIDE 3S technology risk zonation Panxi Area
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Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS 被引量:2
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作者 GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期313-320,共8页
Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present ... Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two key factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones. 展开更多
关键词 GIS the Yellow River Delta saline-alkali land zonation
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The Magma-dynamic Mechaism of Emplacement and Compositional Zonation of the Zhoukoudian Stock, Beijing 被引量:3
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作者 Ma Changqian China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第2期159-173,210-211,共17页
The Zhoukoudian stock in Beijing is a concentric zoned complex intrusive body formed by two successive intrusions. Quartz-diorite formed by the first intrusion is scattered sparsely on the margins of the body, while g... The Zhoukoudian stock in Beijing is a concentric zoned complex intrusive body formed by two successive intrusions. Quartz-diorite formed by the first intrusion is scattered sparsely on the margins of the body, while granodiorite resulting from the second intrusion constitutes the main part of the intrusion. It exhibits three distinct petrographic zones macroscopically, and is chemically characterized by enrichment of high-temperature components, such as Mg, Ca, Sc, Ti, Cr, Mn. Fe and Co, on its border and merely slight enrichment of some low-temperature components, such as Na and Si, in its central part. A series of structural features indicate that the deformation of the intrusion and thermo-metamorphic rocks becomes weaker with an increase of distance from the contact, and that the intrusive body is a product of ballooning or inflating diapiric emplacement. Based on calculations of the density, viscosity and yield strength of magma and the reasonable diffusion constants and oxygen isotopic data, the mechanism of the compositional zonation of the major part of the stock is discussed. It is considered that the Soret effect, combined with double-diffusive convection, can explain the compositional zonation of the intrusion. Calculation of the ascent rates of magma shows that successive upwelling of magma got faster and faster with the progress of time. 展开更多
关键词 The Magma-dynamic Mechaism of Emplacement and Compositional zonation of the Zhoukoudian Stock BEIJING
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Landslide Hazard Zonation in NH-1A in Kashmir Himalaya, India 被引量:4
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作者 R. K. Chingkhei A. Shiroyleima +1 位作者 L. Robert Singh Arun Kumar 《International Journal of Geosciences》 2013年第10期1501-1508,共8页
The paper presents a methodology for landslide hazard zonation mapping using GIS and remote sensing data. The study has been carried out along NH-1A-Udhampur to Banihal in Kashmir Himalaya as this terrain is prone to ... The paper presents a methodology for landslide hazard zonation mapping using GIS and remote sensing data. The study has been carried out along NH-1A-Udhampur to Banihal in Kashmir Himalaya as this terrain is prone to the landslide hazards. The present study has been made to derive and identify the important terrain factors contributing to landslide occurrences in the region and corresponding thematic data layers are generated in GIS domain. These terrain data are collected from the topographic maps, satellite imageries, field visits and available published maps. A GIS database is prepared by digitizing these maps along with tabular data and their corresponding weightage is assigned using Analytic Hierarchy Process (AHP) based criteria ranking method for determining the standardized scores of criteria expressing their factor of importance for a given decision problem in terms of thematic parameters, categories and their normalized weights. Statistically integrating weightages from these thematic maps, a specific landslide hazard map was developed on a GIS platform. The resulting landslide hazard zonation map delineates the area into different zones of six classes of landslide hazard zones i.e., severe, very high, high, moderate, low and very low. 展开更多
关键词 LANDSLIDE HAZARD zonation LANDSLIDE HAZARD Management GIS
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Earthquake Hazard Zonation and Seismotectonics of the Bandar Abbas Area, Zagros, Iran 被引量:8
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作者 Saeedeh Abdolizadeh Zahra Maleki Mehran Arian 《Open Journal of Geology》 2016年第3期210-224,共15页
The study area (Bandar Abbas area) is located in the Zagros fold-thrust belt as part of the Alpine-Himalayan orogenic belt as seismically active belt. This area is located between the Makran accretionary prism and Oma... The study area (Bandar Abbas area) is located in the Zagros fold-thrust belt as part of the Alpine-Himalayan orogenic belt as seismically active belt. This area is located between the Makran accretionary prism and Oman Mountains from east and the Zagros collision belt from west as transition zone. The Zagros fold-thrust belt from the viewpoint of seismicity, is very active and Iran’s major earthquake-prone area. The study area has main active faults and some high magnitude earthquakes occurred in current century. Because the Bandar Abbas area has high seismic activity, the main goal of this research is prepared to earthquake hazard zonation and identify hazardous seismic zones, based on Decision Support System method for define active seismotectonic in this area. The seismotectonic study has been done in 30 - 100 km radius, for Bandar Abbas area. In this research, we used Decision Support System method by in corporate and combine essential data such as seismic data from 1900-2015, Digital Elevation Model of the study area (DEM), surface geology, seismicity parameters, soil classification and location main faults. In this research the Decision Support System (DSS) base on GIS database is used for calculate seismicity parameters. Based on the relative risk of earthquake zonation map, the Bandar Abbas area is located from the north to the East and from the South to the East, in area with high seismic risk (with Orange color). Some small regions with very high relative seismic risk have been limited to these areas with high risk. Also from north to west and from south to west “the study area” is located mainly in the area with earthquake relative risk of in areas with moderate and low relative risk of earthquakes. In the far southwestern region of the study, the small area is located in an area with high and very high seismic relative risk and this case may be due to the activity of the Mountain Front Fault (MFF) and Zagros Fore deep Fault (ZFF). Finally, the study area has been affected by active faults and it causes high vulnerability of the study area in the face of a possible occurrence of earthquakes. Based on of Seismotectonic investigations, there are existed minor faults of the Zagros fault from East to West and in the middle part. This case has been caused some parts in the study area with low and moderate seismic risk to be considered in the face of possible earthquakes and seismic damages, as an area with high seismic risk. 展开更多
关键词 ZAGROS Bandar Abbas Earthquake Hazard zonation Active Faults
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Preliminary slope stability analysis and discontinuities driven susceptibility zonation along a crucial highway corridor in higher Himalaya, India 被引量:1
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作者 Barsa ACHARYA Kripamoy SARKAR +1 位作者 Ashok Kumar SINGH Sowmiya CHAWLA 《Journal of Mountain Science》 SCIE CSCD 2020年第4期801-823,共23页
Identification of failure susceptible slopes through different rock engineering approach is highly valuable in landslide risk management along crucial highway corridors in the high mountainous region. In this study, a... Identification of failure susceptible slopes through different rock engineering approach is highly valuable in landslide risk management along crucial highway corridors in the high mountainous region. In this study, a critical highway(NH-5) segment in higher Himalaya has been investigated using the various rock mass characterization schemes based on detailed field observations. Since the highway corridor is highly susceptible to discontinuities-driven failures, consisting of jointed rock masses;Mean and Combined kinematic feasibility analysis has been performed for 20 highway slopes. Observed slope mass classes have been compared to the feasibility percentage of discontinuities driven failures(wedge, toppling, and planar) and accordingly the kinematic feasibility zonation along highway segment has been done for each as well as overall failure types. Based on the slope mass conditions and discontinuities driven failures probability(%), responsive remedial measures have been proposed for individual highway slopes to ensure safe and uninterrupted transportation. 展开更多
关键词 SLOPE characterization Kinematic analysis Failure zonation map HIMALAYAN HIGHWAYS Landslide SLOPE stability
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Climate warming over 1961–2019 and impacts on permafrost zonation in Northeast China 被引量:1
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作者 Xiaoying Li Huijun Jin +4 位作者 Long Sun Hongwei Wang Ruixia He Yadong Huang Xiaoli Chang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期767-788,共22页
In boreal forest ecosystems, permafrost and forest types are mutually interdependent;permafrost degradation impacts forest ecosystem structure and functions. The Xing’an permafrost in Northeast China is on the southe... In boreal forest ecosystems, permafrost and forest types are mutually interdependent;permafrost degradation impacts forest ecosystem structure and functions. The Xing’an permafrost in Northeast China is on the southern margin of the Eastern Asia latitudinal permafrost body. Under a warming climate, permafrost undergoes rapid and extensive degradation. In this study, the frost-number (Fn) model based on air temperatures and ground surface temperatures was used to predict the distribution of the Xing’an permafrost, and, temporal and spatial changes in air and ground-surface temperatures from 1961 to 2019 are analyzed. The results show that Northeast China has experienced a rapid and substantial climate warming over the past 60 years. The rises in mean annual air and mean annual ground-surface temperatures were higher in permafrost zones than those in the seasonal frost zone. The frost numbers of air and ground-surface temperatures were calculated for determining the southern limit of latitudinal permafrost and for permafrost zonation. The southern limits of discontinuous permafrost, sporadic permafrost, and latitudinal permafrost moved northward significantly. According to the air-temperature frost-number criteria for permafrost zoning, compared with that in the 1960s, the extent of Xing’an permafrost in Northeast China had decreased by 40.6% by the 2010s. With an average rate of increase in mean annual air temperatures at 0.03 ℃ a^(−1), the extent of permafrost in Northeast China will decrease to 26.42 × 10^(4) by 2020, 14.69 × 10^(4) by 2040 and to 11.24 × 10^(4) km^(2) by 2050. According to the ground-surface temperature frost-number criteria, the southern limit of latitudinal permafrost was at the 0.463. From the 1960s to the 2010s, the extent of latitudinal permafrost declined significantly. Due to the nature of the ecosystem-protected Xing’an-Baikal permafrost, management and protection (e.g., more prudent and effective forest fire management and proper logging of forests) of the Xing’an permafrost eco-environment should be strengthened. 展开更多
关键词 Climate warming Permafrost zonation Southern limit of latitudinal permafrost Regional differentiation Mean annual air temperature Mean annual ground surface temperature
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GIS-based Risk Zonation of Rainstorm Disaster in Guizhou Province 被引量:1
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作者 CHEN Zhen-hong1, YANG Yi2, LIU Fang3, 4, WANG Xing-ju1 1. Anshun Meteorological Bureau in Guizhou Province, Anshun 561000, China 2. Lingping County Meteorological Bureau in Guizhou Province, Lingping 5573001, China +1 位作者 3. Geographic Science and Resources Research Institute of Chinese Academy of Sciences, Beijing 100101, China 4. Graduate University of Chinese Academy of Sciences, Beijing 100049, China 《Meteorological and Environmental Research》 CAS 2011年第4期60-64,共5页
[Objective] This paper aimed to study the risk zoning of rainstorm in Guizhou based on GIS. [Method] Taking Guizhou as study area, 1 km×1 km grid data as evaluation unit, and by dint of daily precipitation in met... [Objective] This paper aimed to study the risk zoning of rainstorm in Guizhou based on GIS. [Method] Taking Guizhou as study area, 1 km×1 km grid data as evaluation unit, and by dint of daily precipitation in meteorological station in Guizhou from 1961 to 2008, the rainstorm risk zoning system was constructed from the aspects of disaster-stricken dangers, suffering flexibility, disaster environment sensitivity and disaster prevention or mitigation; based on the level analysis method to determine factor weight, the risk assessment model based on GIS was set up to evaluate the four sub-indicators and risks and to get the rainstorm disaster in Guizhou in the end. [Result] The risk assessment and zonation results showed a general trend that the risk level decreased from the central to all around. The low risk area distributed in the northwest of Guizhou province because of less heavy rains and high capacity of rainstorm disaster resistant, while high risk area mainly distributed in the west-central of Guizhou due to concentration rainstorms, large terrain undulation and low coverage rate of forest. Especially, according to Anshun, the high risk area took up 98.02% of the city, and the Gangwu County, where a super-large geological disaster concurred in 2010 is located at the high risk area, which showed that the risk assessment coincided with the actual situation. [Conclusion] The study provided theoretical basis for the macro disaster prevention and disaster mitigation plan. 展开更多
关键词 Rainstorm disaster Risk assessment and zonation AHP GIS GUIZHOU China
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Zonation and Prediction of Land Subsidence (Case Study-Kerman, Iran) 被引量:1
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作者 Seyed Mahmood VaeziNejad Mohamad Mohsen Tofigh Seyed Morteza Marandi 《International Journal of Geosciences》 2011年第2期102-110,共9页
Drought and Immethodical ground water withdrawal in recent years has caused numerous problems such as subsidence due to falling of subsurface water table, the reduction of water quality, etc. in cities across the worl... Drought and Immethodical ground water withdrawal in recent years has caused numerous problems such as subsidence due to falling of subsurface water table, the reduction of water quality, etc. in cities across the world. This research as a case study deals with harmful effects of subsurface water withdrawal in the city of Kerman and practical monitoring of the subsidence and makes prediction of land subsidence. The artificial neural network has been used for modeling the monitored results and prediction of future subsidence. A surveying network with more than 500 installed benchmarks in an area of 334 square kilometer has been used to measure the subsidence of the city area. Benchmarks were installed in the beginning of 2004 and were monitored at the end of 2004, 2006, and 2007. For modeling, extra data were obtained from Iranian Surveying Organization for the years before 2004. The resulting model showed that, the subsidence varies between zero and 15cm per year in different parts of the City, which depends on the subsurface-layered soils, their compressibility, and the manner of subsurface water withdrawal. 展开更多
关键词 Land SUBSIDENCE zonation SUBSURFACE Water WITHDRAWAL Artificial Neural Network SUBSIDENCE PREDICTION
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A Seismotectonic Zonation Map of Eastern Siberia: New Principles and Methods of Mapping 被引量:1
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作者 L. P. Imaeva V. S. Imaev +1 位作者 O. P. Smekalin N. N. Grib 《Open Journal of Earthquake Research》 2015年第4期115-125,共11页
The paper reviews goals and objectives, stages and components of a seismotectonic study conducted in Eastern Siberia, Russia. Based on a comprehensive analysis of geological and geophysical data, our study establishes... The paper reviews goals and objectives, stages and components of a seismotectonic study conducted in Eastern Siberia, Russia. Based on a comprehensive analysis of geological and geophysical data, our study establishes whether the local earthquakes are of tectonic origin and reveals relationships among earthquakes with recent geodynamic processes in the area under study. Seismic hazard assessment and evaluation of tectonic processes are the two major closely interrelated aspects of seismotectonic studies. A seismotectonic study is generally combined with a seismic study and conducted prior to the stage of detailed seismic zonation (DSZ) which is followed by seismic micro-zonation (SMZ). In three stages of the seismotectonic study, we analyze specific geological structures, reveal the regional dynamics of seismotectonic processes, clarify details of potential seismic hazard locations and identify sites of the potential instantaneous deformation of the crust which may take place due to active faulting. Based on results of our longterm studies, a seismotectonic zonation map of Eastern Siberia is compiled. The paper briefly reviews the methods of mapping and refers to data on active faults and neotectonic structures revealed in the area under study, which are closely related to regional earthquake sources. 展开更多
关键词 SEISMOTECTONIC Studies SEISMIC Hazard Active Faults Geological and Geomorphological METHODS TRENCHING SEISMIC Source Zones SEISMIC BELTS SEISMIC Belt Segments SEISMOTECTONIC zonation Map of Eastern Siberia
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UNCERTAINTY ANALYSIS ON ZONATION MAPS OF DEBRISFLOW HAZARD IN YUNNAN PROVINCE,CHINA
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作者 LIU Xi-lin(Dapartment of Urban and Environmental Scicnces, Peking University Beijing 100871, P.R.China Institute of Moun tain Hazards and Environment, the Chinese Academy of Sicnces, Chengdu 610041,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期138-143,共6页
Different researchers select different factors and use different methods to assess the regional hazard degrees of debris now. consequenily, even for the same region, tb.. are often different hazard zonation maps, and ... Different researchers select different factors and use different methods to assess the regional hazard degrees of debris now. consequenily, even for the same region, tb.. are often different hazard zonation maps, and there must be some uncertainty in the zonations. Thus the ceriainty analysis of zonation maps becomes obviously important.For debris now hazard, those zonation maps with a certainty analysis could provide most valuable information for land users, hazard managers and policy makers. By comparison of three researchers’ findings in Yunnan Province, this paPer shows that seven to nine iafluential factors are chosen for the zonation maps. spatial density of debris flow ravines,regional average rock-weathering coefficient, yearly precipitation, days of≥50 mm daily rainfall, and proportion of sloping land with slope≥25℃to the total land are the most acceptable factors. Mathemahcal methods of maximum-minimumvalues, upperlower limit values and Fuzzy values are used to quantify the factors. Step-by-step methodoogy is commonly used for the zonation maps. Research results show that mchmum uncedrinty is 66. 6% and minimum uncertainty is 35.7% in debris now hazard maps of zhaotong Prefecture and Yunnan Province. Therefore there is still much work for us to improve the zonation methedology. 展开更多
关键词 DEBRIS flow HAZARD zonation UNCERTAINTY zonation MAP
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