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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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Durability zonation standard of concrete structure design 被引量:5
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作者 金伟良 吕清芳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期98-104,共7页
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an... Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation. 展开更多
关键词 durability zonation standard concrete structure design zonation map life cycle cost
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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:39
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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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Liver zonation: Novel aspects of its regulation and its impact on homeostasis 被引量:5
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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 localizatio... 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 &#x0201c;omics&#x0201d; 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 Morphogen signalling Optimization Pathology Regulatory network SINUSOID Systems biology
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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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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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Geoscience landscape division and tourism zonation in the mid-southern section of the Hengduan Mountains, eastern Qinghai-Tibet Plateau 被引量:3
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作者 CHEN Xing SHI Xian-lin 《Journal of Mountain Science》 SCIE CSCD 2018年第4期894-917,共24页
The mid-southern section of the Hengduan Mountains is a typical region of mountainous landscape in western China and is the core region of "Shangri-La", a world-famous ecotourism destination. The landscape c... The mid-southern section of the Hengduan Mountains is a typical region of mountainous landscape in western China and is the core region of "Shangri-La", a world-famous ecotourism destination. The landscape classification system is an important scientific basis for landscape protection and tourism development in this region. By combining geology and geography and referring to the concepts of "system tract" and "tectonic system" in geology, this paper comes up with grading standards for the geoscience landscape system of this region. Based on the regional stratigraphic structure, tectonic fault marks and geomorphological differentiation, this paper comes up with 2 Grade Ⅰ geoscience landscape system tracts, 8 Grade Ⅱ geoscience landscape systems, 21 Grade Ⅲ geoscience landscape areas, and 165 representative Grade Ⅳ geoscience landscape attractions. According to the main classification methods for the geological heritage and tourism landscapes, the geoscience landscapes can be divided into 4 categories, 16 types and 19 subtypes. On this basis, 23 eco-tourism areas of the mid-southern section of the Hengduan Mountains can be delimited. The study provides a theoretical direction and method reference for the geoscience landscape division and tourism zonation, which has an importantsignificance on the mountain landscape protection and tourism development in the regions of complex geo-environments. 展开更多
关键词 Geoseience landscape Landscape system Tourism zonation High mountain canyon area Hengduan Mountains
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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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Landslide Hazard Zonation Mapping and Comparative Analysis of Hazard Zonation Maps 被引量:3
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作者 S.Sarkar R.Anbalagan 《Journal of Mountain Science》 SCIE CSCD 2008年第3期232-240,共9页
Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the l... Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the landslide hazards. The main objective of the present work was to carry out macro landslide hazard zonation mapping on 1:50,000 scale in an area where regional level zonation mapping was conducted earlier. In the previous work the regional landslide hazard zonation maps of Srinagar-Rudraprayag area of Garhwal Himalaya in the state of Uttarakhand were prepared using subjective and objective approaches. In the present work the landslide hazard zonation mapping at macro level was carried out in a small area using a Landslide Hazard Evaluation Factor rating scheme. The hazard zonation map produced by using this technique classifies the area into relative hazard classes in which the high hazard zones well correspond with high frequency of landslides. The results of this map when compared with the regional zonation maps prepared earlier show that application of the present technique identified more details of the hazard zones, which are broadly shown in the earlier zonation maps. 展开更多
关键词 LANDSLIDES Hazard zonation Garhwal Himalaya MAPPING
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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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Using Statistical Learning Algorithms in Regional Landslide Susceptibility Zonation with Limited Landslide Field Data 被引量:2
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作者 WANG Yi-ting SEIJMONSBERGEN Arie Christoffel +1 位作者 BOUTEN Willem CHEN Qing-tao 《Journal of Mountain Science》 SCIE CSCD 2015年第2期268-288,共21页
Regional Landslide Susceptibility Zonation(LSZ) is always challenged by the available amount of field data, especially in southwestern China where large mountainous areas and limited field information coincide. Statis... Regional Landslide Susceptibility Zonation(LSZ) is always challenged by the available amount of field data, especially in southwestern China where large mountainous areas and limited field information coincide. Statistical learning algorithms are believed to be superior to traditional statistical algorithms for their data adaptability. The aim of the paper is to evaluate how statistical learning algorithms perform on regional LSZ with limited field data. The focus is on three statistical learning algorithms, Logistic Regression(LR), Artificial Neural Networks(ANN) and Support Vector Machine(SVM). Hanzhong city, a landslide prone area in southwestern China is taken as a study case. Nine environmental factors are selected as inputs. The accuracies of the resulting LSZ maps are evaluated through landslide density analysis(LDA), receiver operating characteristic(ROC) curves and Kappa index statistics. The dependence of the algorithm on the size of field samples is examined by varying the sizes of the training set. The SVM has proven to be the most accurate and the most stable algorithm at small training set sizes and on all known landslide sizes. The accuracy of SVM shows a steadilyincreasing trend and reaches a high level at a small size of the training set, while accuracies of LR and ANN algorithms show distinct fluctuations. The geomorphological interpretations confirm the strength of SVM on all landslide sizes. Our results show that the strengths of SVM in generalization capability and model robustness make it an appropriate and efficient tool for regional LSZ with limited landslide field samples. 展开更多
关键词 Landslide Susceptibility zonation(LSZ) Logistic Regression(LR) Artificial Neural Network(ANN) Support Vector Machine(SVM) Regional scale Southwest China
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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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Durability related environmental zonation and design methodology for marine RC structures 被引量:1
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作者 Wu Hairong Lü Qingfang Jin Weiliang 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期78-86,共9页
A reliability-based quantitative durability design methodology is presented for reinforced concrete(RC)structures in the marine environment on the basis of natural exposure data derived from four berths(1.5,1.5,4 and ... A reliability-based quantitative durability design methodology is presented for reinforced concrete(RC)structures in the marine environment on the basis of natural exposure data derived from four berths(1.5,1.5,4 and 15 years)of a concrete port.More than 200 chloride profiles are obtained and analyzed.The relationship between nominal surface chloride ion concentration and altitude is discussed.Subsequently,the formula of the apparent chloride diffusion coefficient is proposed with consideration of the surrounding temperature,sodium chloride solution concentration,age factor and altitude.Then,the reliability-based method to predict the durability of RC structures is developed according to Fick s second law.Relationships between the predicted penetration depth of the chloride ion,the ratio of the wetting time per-period and the corresponding altitude are discussed.Subsequently,the environmental zonation methodology is established for concrete structures under a marine chloride environment by considering the ratio of the wetting time per-period of concrete as the zoning index.Finally,the corres-ponding durability design method for each zone level is established,which contains the durability design regulations of the specimen,and correction coefficients for different water/binder ratios,ages,temperatures and chloride ion concentrations. 展开更多
关键词 reinforced concrete structure MARINE chloride ion ENVIRONMENT zonation durability design
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