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61.
应用等效纬度-海拔模型进行地温及多年冻土制图   总被引:2,自引:2,他引:2  
This research presents a method for permafrost mapping in discontinuous permafrost regions based on equivalent latitude/elevation concept in interior Alaska. In winter months, study site has a strong temperature inversion in air up to 700 m elevation. Air temperature data and the effects of slope, aspect and elevation were used to create an equivalent latitude/elevation model. This model was well correlated with mean annual surface temperature (0.79). In this watershed, the thawing index (It≈1 400 ℃*days) at the ground surface and snow depth do not vary greatly from south facing to north facing slopes. The primary controlled factor that determines the mean annual surface temperature was the winter surface temperature. The permafrost stability is effectively controlled by the freezing index. We determined 37.5% of Caribou-Poker Creeks Research Watershed has unstable or thawing permafrost. At least 2.1% of the permafrost in this watershed may have disappeared in the last 90 years due to climate warming. This method makes it possible to evaluate the permafrost stability in the present, past and future.  相似文献   
62.
编制中国76种元素地球化学图将使我们首次了解元素周期表上除氢、氧及惰性气体之外所有元素在中国大陆表层的分布,川滇黔桂76种元素地球化学图的编制是这一研究项目的试点。本文以不同实验室取得的Ag、Cs、Ga、Ge分析数据为例,探索、衡量不同实验室地球化学图相似性的方法,以优选实验室进行川滇黔桂4省区约4000件组合样76种元素的大规模分析工作。  相似文献   
63.
本文以 1∶5万里庄幅为例 ,阐述了运用GIS系统对区调过程中各种资料的处理与编辑方法 ,并介绍了数字制图方法及工艺流程 ,提出了GIS系统在 1∶5万区调工作中的应用前景  相似文献   
64.
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   
65.
According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN)real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system′s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type and hazardous zone, the torrent management, the early-warning of disasters and the disaster reduction and prevention.  相似文献   
66.
This paper presents a statistical approach to study the spatial relationship between landslides and their causative factors at the regional level. The approach is based on digital databases, and incorporates such methods as statistics, spatial pattern analysis, and interactive mapping. Firstly, the authors propose an object-oriented conceptual model for describing a landslide event, and a combined database of landslides and environmental factors is constructed by integrating the various databases within such a conceptual framework. The statistical histogram, spatial overlay, and dynamic mapping methods are linked together to interactively evaluate the spatial pattern of the relationship between landslides and their causative factors. A case study of an extreme event in 1993 on Lantau Island indicates that rainfall intensity and the migration of the center of the rainstorm greatly influence the occurrence of landslides on Lantau Island. A regional difference in the relationship between landslides and topography is identified. Most of the landslides in the middle and western parts of the island occurred on slopes with slope angles of 25–35°, while in the eastern part, the corresponding range is 30–35°. Overlaying landslide data with land cover reveals that a large number of landslides occurred in the bareland and shrub-covered area, and in the transition zones between different vegetation types. The proposed approach can be used not only to analyze the general characteristics of such a relationship, but also to depict its spatial distribution and variation, thereby providing a sound basis for regional landslide prediction.  相似文献   
67.
GRAPHER、Surfer32与CorelDRAW1O在物探成图中的应用   总被引:1,自引:0,他引:1  
用GRAPHER、Surfer32软件作出给定数据的曲线图、平剖图、平面等值线图和立体曲面图后,再用CorelDRAW10来编辑,可快速做出一张满意而又少占存储空间的图件。  相似文献   
68.
地质论文中的插图具有自身的特殊性,根据地质科技期刊对其插图的要求,应用各种绘图软件制作插图,经对比认为MAPGIS是一种方便、快捷、功能强大、最适合制作地质插图的矢量化软件。  相似文献   
69.
我国数字填图技术研究现状与发展趋势   总被引:5,自引:0,他引:5  
李超岭 《新疆地质》2003,21(Z1):1-6
数字填图系统(RGMAP)是中国地质调查局研发的,用来进行区域地质调查工作的专业软件.通过4幅150000和10幅1250000数字填图试点应用,使数字填图系统已臻于完善,为中国地质调查局全面推广数字填图方法奠定了良好的基础.野外数据采集数字化,使得地质调查数据实现了一体化的描述、组织、综合、管理及资源的统一描述、再现和集成.建立个性化的多用户,多目标的社会化服务体系,是今后地质调查主流程信息化的主要任务和目标.  相似文献   
70.
全球地球化学填图   总被引:19,自引:10,他引:19       下载免费PDF全文
作指出了1973年至今世界上50余项地球化学填图计划中普遍存在的缺陷大都涉及分析问题。1988-1992年实施的国际地质对比计划IGCP259项目旨在使全世界地球化学填图方法标准化。在此项目中对分析问题提出了若干规定,主要是要求今后的填图计划应统一分析71种元素,痕量及超痕量元素的检出限必须低于相应的地壳丰度值及采用中国的GSD和加拿大的STSD标样系列,以使全球数据可以对比,在其后开始延续至今的全球地球化学填图计划IGCP360,旨在用极低密度采样早日覆盖全球大陆,讨论了正在实行的两种极低密度采样方案,并提出通过极低密度采集地极少量样品示范性实现IGCP259项目对分析要求的具体建议。  相似文献   
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