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1.
Mineral potential within the Greater Nahanni Ecosystem (GNE) was modelled in a Geographic Information System (GIS) for four different deposit types: (1) SEDEX (stratiform shale-hosted sedimentary exhalative Zn–Pb–Ag), (2) ‘Carbonate-Fault’ (carbonate-hosted zinc–lead–silver associated with major faults), (3) ‘Intrusion-Related’ (includes skarn, rare metals and gemstones) and (4) Carlin-Type gold as lode and/or derived placer deposits. This mineral potential modelling study integrates data collected during the Nahanni Mineral and Energy Resource Assessment (MERA) undertaken from 2003 to 2007. The results have contributed to the process of determining the geographic boundaries of the proposed expansion of the Nahanni National Park Reserve. Four mineral potential maps were produced (one for each deposit type) using a knowledge-driven approach. A weighting scheme based on integrated mineral deposit and regional geological knowledge was derived for the various evidence maps for each deposit model using expert opinion. The four potential maps were then combined into a final potential map using a maximum operator. Plots showing the efficiency of the models (mineral potential maps) for predicting the known occurrences of the four deposit types show that partial data sets provide reasonable predictions of the remaining known mineral prospects, occurrences and deposits. Hydrocarbon potential from Nahanni MERA 1 was added to the final potential map to ensure that both mineral and energy potential data were incorporated into the park configuration modelling.  相似文献   

2.
地理专家系统的试验研究   总被引:18,自引:0,他引:18  
马蔼乃  周长发 《地理学报》1992,47(3):252-259
80年代人工智能与地理学的结合产生了地理专家系统(GES)。地理专家系统是继地理信息系统之后,对地理知识与推理形式化,建立的具有一定地理专业水平的计算机软件系统。地理专家系统由地理数据库,地理知识库和地理推理机三大部分组成。地理数据库是GES的数据管理模块,我们设计了一套地理信息系统MCGIS来作为微机地理专家系统MCGES的综合数据库;地理知识库是GES的知识管理模块;地理推理机则是GES的推理控制策略的程序体现。本文结合一个用C语言自行设计的基于规则的产生式微机地理专家系统MCGES阐述了地理专家系统的原理和方法。  相似文献   

3.
地理专家系统的应用现状及发展趋势综述   总被引:3,自引:0,他引:3  
地理专家系统是专家系统与地理信息系统结合的产物。该文介绍了地理专家系统的概念、框架结构等基础内容,从地理知识库、空间知识发现、推理机制、G1S与ES集成四方面阐述了地理专家系统的研究现状及进展,提出地理专家系统存在的问题及发展趋势。  相似文献   

4.
The inherent problems of classifying or inventorying potential mineral resources (as opposed to known mineral resources) pose specific challenges. In this paper, the application of a conceptual mineral exploration model and GIS to generate mineral potential maps as input to land-use policy decision-making is illustrated. We implement the criteria provided by a conceptual exploration model for nickeliferous-laterites by using a GIS to classify the nickeliferous-laterite potential of an area in the northeastern part of the Philippines. The spatial data inputs to the GIS are geological map data, topographic map data, and stream sediment point data. Processing of these data yields derivative maps, which are used as indicators of nickeliferous-laterite potential. The indicator maps then are integrated to furnish a nickeliferous-laterite potential map. This map is compared with present land-use classification and policy in the area. The results indicate high potential for nickeliferous-laterite occurrence in the area, but the zones of potential are in places where mineral resources development is prohibited. The prohibition was imposed before the nickeliferous-laterite potential was assessed by this study. Mineral potential classification therefore is a critical input to land-use policy-making so that prospective land is not alienated from future mineral resource development.  相似文献   

5.
智能化制图综合在GIS环境下的实现方法研究   总被引:7,自引:1,他引:6  
自动制图综合的研究长期以来未能取得突破性进展,原因之一是人们对制图综合的知识处理的深度不够。本文探讨在GIS环境下实现智能化制图综合的方法。方法要点是:①采用知识推理+数学模型的方法,即将基于专家知识的智能化推理与数学模型处理结合起来,用知识推理引导和操纵数学模型处理,以期达到较理想的结果;②在专家知识规则中贯穿面向地理特征的思想,即包括面向地理要素、面向地物对象-类,面向特殊地理区域等方面的知识法则。本文首先阐述在GIS环境下实现智能化制图综合功能的策略,其次描述知识推理控制下的数学模型操作流程,以及制图综合专家知识库的组织形式;最后阐述各种面向地理特征的制图综合知识规则。  相似文献   

6.
《The Journal of geography》2012,111(3):109-122
Abstract

This research was based on an instructional module developed and used to investigate whether GIS can be used to enhance fourth grade students' geographic knowledge and map skills. Another goal was to identify challenges the teachers and the students face using GIS.

Findings from the study suggest that using GIS in the classroom helps students improve their geographic knowledge and maps skills. In addition, this study found that the students' geographic content knowledge tended to improve gradually and the knowledge transferred to the subsequent lessons, while certain map skills tended to develop in a more specific manner.  相似文献   

7.
Abstract

Development programmes in Sahelian Africa are beginning to use geographic information system (GIS) technology. One of the GIS and remote sensing programmes introduced to the region in the late 1980s was the use of seasonal vegetation maps made from satellite data to support grasshopper and locust control. Following serious outbreaks of these pests in 1987, the programme addressed a critical need, by national and international crop protection organizations, to monitor site-specific dynamic vegetation conditions associated with grasshopper and locust breeding. The primary products used in assessing vegetation conditions were vegetation index (greenness) image maps derived from National Oceanic and Atmospheric Administration satellite imagery. Vegetation index data were integrated in a GIS with digital cartographic data of individual Sahelian countries. These near-real-time image maps were used regularly in 10 countries for locating potential grasshopper and locust habitats. The programme to monitor vegetation conditions is currently being institutionalized in the Sahel.  相似文献   

8.
地理专家知识表示的框架网络模型研究   总被引:1,自引:0,他引:1  
付炜 《地理研究》2002,21(3):357-364
基于框架网络结构模型的专家知识表示方法 ,采用知识的框架网络结构描述地学环境的实体单元 ,将各级专家知识的表示以指针连接 ,形成了由知识到语义的专家知识表示的框架网络。以乌鲁木齐河流域土地合理利用规划决策专家系统的构建为例 ,阐述了该模型的构造方法和实现方案 ,并讨论了系统知识库的组织结构和推理规则的设计原理。  相似文献   

9.
I.IntroductionUsingcomputertomakestatisticalcharthascurrentlybecomeverypopular(LiandZhang,1981),butinmanysocialandeconomicactivitiessuchasnationaleconomicmanagementanddecisionmaking,aconsiderablepartofstatisticaldataiscollectedwithinacertainadministrative…  相似文献   

10.
地理遥感信息模型   总被引:28,自引:0,他引:28  
马蔼乃 《地理学报》1996,51(3):266-271
地理遥感信息模型是作者在地形模型,物理模型,数学模型的基础上提出一种新型模型,本文概述了地理遥感信息模型的基本概念和分类。  相似文献   

11.
Quantitative prediction and evaluation of mineral resources are one of the important topics of mathematical geology. On the basis of GIS technologies and weights of evidence modeling, MapGIS is integrated with GIS and mineral-resource prediction and evaluation. The final product is a predictor map of posterior probabilities of occurrence of the discrete event within a small unit cell. Predictor layers were created on a digital database that includes 1:200,000 scale geological, and geochemical, and geophysical maps, and remote-sensing images in study area. According to metallogenetic factors extractiont and weights of evidence modeling, there are four main metal ore belts in the study area: (1) the Batang belt; (2) the Lei Wuqi belt; (3) the Basu-Chayu belt; and (4) the Ganzi-Litang belt. The predictor map of posterior probabilities show that 29% of study area as zones with potential for porphyry copper, and 81% known mineral occurrences success rate is circled in the metallogenetic posterior probabilities map. The results demonstrate plausibility of weights-of-evidence modeling of mineral potential in large areas with small number of mineral prospects.  相似文献   

12.
The U.S. Geological Survey (USGS) is proposing to conduct a global mineral-resource assessment using geologic maps, significant deposits, and exploration history as minimal data requirements. Using a geologic map and locations of significant pluton-related deposits, the pluton-related-deposit tract maps from the USGS national mineral-resource assessment have been reproduced with GIS-based analysis and modeling techniques. Agreement, kappa, and Jaccard's C correlation statistics between the expert USGS and calculated tract maps of 87%, 40%, and 28%, respectively, have been achieved using a combination of weights-of-evidence and weighted logistic regression methods. Between the experts' and calculated maps, the ranking of states measured by total permissive area correlates at 84%. The disagreement between the experts and calculated results can be explained primarily by tracts defined by geophysical evidence not considered in the calculations, generalization of tracts by the experts, differences in map scales, and the experts' inclusion of large tracts that are arguably not permissive. This analysis shows that tracts for regional mineral-resource assessment approximating those delineated by USGS experts can be calculated using weights of evidence and weighted logistic regression, a geologic map, and the location of significant deposits. Weights of evidence and weighted logistic regression applied to a global geologic map could provide quickly a useful reconnaissance definition of tracts for mineral assessment that is tied to the data and is reproducible.  相似文献   

13.
An application of the theory of fuzzy sets to the mapping of gold mineralization potential in the Baguio gold mining district of the Philippines is described. Proximity to geological features is translated into fuzzy membership functions based upon qualitative and quantitative knowledge of spatial associations between known gold occurrences and geological features in the area. Fuzzy sets of favorable distances to geological features and favorable lithologic formations are combined using fuzzy logic as the inference engine. The data capture, map operations, and spatial data analyses are carried out using a geographic information system. The fuzzy predictive maps delineate at least 68% of the known gold occurrences that are used to generate the model. The fuzzy predictive maps delineate at least 76% of the unknown gold occurrences that are not used to generate the model. The results are highly comparable with the results of previous stream-sediment geochemical survey in the area. The results demonstrate the usefulness of a geologically constrained fuzzy set approach to map mineral potential and to redirect surficial exploration work in the search for yet undiscovered gold mineralization in the mining district. The method described is applicable to other mining districts elsewhere.  相似文献   

14.
Abstract

Mapping forest soils using conventional methods is time consuming and expensive. An expert system is described and applied to the mapping of five forest soil-landscape units formed on a single granitoid parent material. Three thematic maps were considered important in influencing the distribution of soils. The first showed the distribution of nine classes of native eucalypt forests, and the second and third were derived from a digital elevation model and represented slope gradient and a soil wetness index combined with topographical position. These layers were input to a raster based geographical information system (GIS) and then geometrically co-registered to a regular 30 m grid. From a knowledge of soil distributions, the relationships between the soil-landscape units and the three data layers were quantified by an experienced soil scientist and used as rules in a rule based expert system. The thematic layers accessed from the GIS provided data for the expert system to infer the forest soil-landscape unit most likely to occur at any given pixel. The soil-landscape map output by the expert system compared favourably with a conventional soil-landscape map generated using interpretation of aerial photographs.  相似文献   

15.
Estimates of numbers of undiscovered mineral deposits, fundamental to assessing mineral resources, are affected by map scale. Where consistently defined deposits of a particular type are estimated, spatial and frequency distributions of deposits are linked in that some frequency distributions can be generated by processes randomly in space whereas others are generated by processes suggesting clustering in space. Possible spatial distributions of mineral deposits and their related frequency distributions are affected by map scale and associated inclusions of non-permissive or covered geological settings. More generalized map scales are more likely to cause inclusion of geologic settings that are not really permissive for the deposit type, or that include unreported cover over permissive areas, resulting in the appearance of deposit clustering. Thus, overly generalized map scales can cause deposits to appear clustered. We propose a model that captures the effects of map scale and the related inclusion of non-permissive geologic settings on numbers of deposits estimates, the zero-inflated Poisson distribution. Effects of map scale as represented by the zero-inflated Poisson distribution suggest that the appearance of deposit clustering should diminish as mapping becomes more detailed because the number of inflated zeros would decrease with more detailed maps. Based on observed worldwide relationships between map scale and areas permissive for deposit types, mapping at a scale with twice the detail should cut permissive area size of a porphyry copper tract to 29% and a volcanic-hosted massive sulfide tract to 50% of their original sizes. Thus some direct benefits of mapping an area at a more detailed scale are indicated by significant reductions in areas permissive for deposit types, increased deposit density and, as a consequence, reduced uncertainty in the estimate of number of undiscovered deposits. Exploration enterprises benefit from reduced areas requiring detailed and expensive exploration, and land-use planners benefit from reduced areas of concern.  相似文献   

16.
GIS空间数据库的"一库两用"策略研究   总被引:2,自引:0,他引:2  
GIS有两种普遍的应用需求:空间分析和数字制图,但两种需求对空间数据的要求不完全一致,导致空间数据在同一GIS中无法充分共享。该文探讨能够同时满足两种需求的GIS构建方法。分析地理空间数据存在的冲突,引入"一库两用"思想,建立空间分析型数据模型;利用专家系统机制实现空间分析数据向数字制图数据的转换,转换过程中补充的信息源于专家知识库。该研究有助于解决GIS中数据不一致问题,使GIS更实用、功能更完善。  相似文献   

17.
Harris  J. R.  Wilkinson  L.  Heather  K.  Fumerton  S.  Bernier  M. A.  Ayer  J.  Dahn  R. 《Natural Resources Research》2001,10(2):91-124
A Geographic Information System (GIS) is used to prepare and process digital geoscience data in a variety of ways for producing gold prospectivity maps of the Swayze greenstone belt, Ontario, Canada. Data used to produce these maps include geologic, geochemical, geophysical, and remotely sensed (Landsat). A number of modeling methods are used and are grouped into data-driven (weights of evidence, logistic regression) and knowledge-driven (index and Boolean overlay) methods. The weights of evidence (WofE) technique compares the spatial association of known gold prospects with various indicators (evidence maps) of gold mineralization, to derive a set of weights used to produce the final gold prospectivity map. Logistic regression derives statistical information from evidence maps over each known gold prospect and the coefficients derived from regression analysis are used to weight each evidence map. The gold prospectivity map produced from the index overlay process uses a weighting scheme that is derived from input by the geologist, whereas the Boolean method uses equally weighted binary evidence maps.The resultant gold prospectivity maps are somewhat different in this study as the data comprising the evidence maps were processed purposely differently for each modeling method. Several areas of high gold potential, some of which are coincident with known gold prospects, are evident on the gold prospectivity maps produced using all modeling methods. The majority of these occur in mafic rocks within high strain zones, which is typical of many Archean greenstone belts.  相似文献   

18.
Justin Wood 《Area》2005,37(2):159-170
Communities can be encouraged to participate in countryside conservation through mapping, expressing what they feel to be important or distinct locally. Established UK community 'parish map' projects focus on artwork. 'Public participation geographic information systems' potentially offer an alternative community mapping approach. Research sought to compare artwork and GIS mapping and their ease of use. Raster maps, digitizing of features and data table creation encouraged community groups to undertake thematic mapping themselves. Seamless maps removed perceived neighbourhood boundaries. Linking attribute data to maps offers an interactive approach to projects, including internet mapping. Findings indicated that hands-on use of GIS, with support, could benefit and empower community groups when responding to local geographic issues.  相似文献   

19.
中国古地图遗产与文化价值   总被引:1,自引:0,他引:1  
梁启章  齐清文  姜莉莉  张岸  梁迅 《地理学报》2016,71(10):1833-1848
中国古地图学创于公元三世纪《西晋·裴秀传》提出的“制图之体有六焉”,被西方誉为中国地图学之父的裴秀(西晋司空),领衔制作了《禹贡地域图》十八篇和《地形方丈图》(公元224-271年)。其后的1600年间,先后完成了一批著名的中国古地图,例如南朝大臣谢庄领衔完成的”木方丈图”(公元502-557年)、隋炀帝命学者崔绩(550-618年)撰《区宇图志》(公元581-600年)、唐朝宰相贾耽领衔绘制《海内华夷图》(公元730-805年)、北宋科学家沈括领衔绘制《守令图》(公元1031-1095年)、南宋礼部尚书黄裳绘制《苏州石刻天文图》原图(公元1190年)、元代玄教宗师朱思本制作《舆地图》(公元1273-1333年)、明代航海家郑和领衔完成《郑和航海图》与地理学家罗洪先领衔制作《广舆图》(公元1504-1564年)、明代天文学家徐光启等完成的《恒星屏障图》、清代高邮知州魏源受林则徐委托编撰《海国图志》(公元1842-1852年)等,继承与发展了独特的中国古代地图学,即使西方经纬度制图技术于公元1584-1600年前后传至中国,启动了中西地图融合发展,中西两种制图理论和方法并行地使用了400余年。闻名中外的中国古地图,包括古天文图、世界图、中国图、航海图、区域图、水利图、军事图、风景名胜图、历史图、教育图等,迄今仍被国内外著名藏图机构分散地保存着,构成了世界古地图文化遗产中的重要组成部分,具有十分珍贵的文化价值,值得进一步深入探讨、挖掘和利用。本文最后初步地探讨了中国古地图的稀有价值、应用价值、历史价值、科学价值和艺术价值。  相似文献   

20.
根据士地覆盖动态监测的需求,设计了重分类方法,对遥感土地覆盖分类图及坡度分类图进行了分类码的设计和GIS数据建库的讨论,通过信息叠加可以得到所需要的信息,进而可以分析不同土地类型及在不同坡度类型下地类之间的相互转化规律.方法应用于澜沧江梯级电站库区,对1988年、1996年和2000年的土地覆盖资料进行了分析,并通过野外实地调查资料进行验证,得出该区土地覆盖时空变化规律,进而可以为该区人类活动和环境之间相互关系与产沙机理提供分析依据,表明信息重分类方法在土地覆盖动态变化监测及其他相关领域具有十分重要的应用价值.  相似文献   

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