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101.
航空物探平剖图自动绘制的可视化处理   总被引:5,自引:2,他引:5  
刘浩军 《物探与化探》2004,28(2):147-149
简要介绍了航空物探平面剖面图的自动绘制方法,给出了绘制中对一些问题的处理方法;重点介绍了彩色渐变填充着色、彩色渐变渲染着色等几种可视化处理方法,并提出了着色中渐变度、透明度概念及应用方法。  相似文献   
102.
在MAPGIS下快速实现柱状剖面图的绘制   总被引:4,自引:0,他引:4  
将油气化探数据用FORTRAN短程序生成MAPGIS点、线、面明码文件后,再利用MAPGIS图形编辑软件对图形进行编辑加工,达到快速制作油气化探柱状剖面图的目的。使用该方法能充分利用MAPGIS系统资源,降低编制绘图程序的难度。  相似文献   
103.
杨书辰  宫进忠  董杰 《物探与化探》2004,28(1):23-25,31
以现代地层学多重划分为理论依据,以岩石地层单元组的密度、磁化率、剩余磁化强度及厚度加权算术平均值等物性参数为研究对象,以有序地质量最优分割方法为数学手段,进行河北省全区综合地层柱物理地层界线的厘定,并对其地质意义进行了初步讨论。  相似文献   
104.
Abstract. Recent discoveries of seafloor hydrothermal mineralization in submarine volcanic centers of felsic magma in western Pacific island arcs are regarded as modern analogues of Kuroko type deposits. Studies of these deposits and their surrounding geology raised question whether the exploration activity for the Kuroko deposits on land which peaked in the 1960's was adequate or not. However, such an evaluation is not easy because the exploration data are about to be lost as a result of the closure of all the Kuroko mines in the area since 1994.
The Metal Mining Agency of Japan (MMAJ), therefore, decided to compile existing data on about 180 Kuroko deposits and related mineral occurrences in northeast Japan as a new Kuroko database.
This study extends a concept called "exploration indices" which was developed based on a case study of the thoroughly surveyed Hokuroku district to draw a potential map of the Kuroko occurrences for the entire northeast Japan quantitatively with a Geographical Information System (GIS). Effective exploration indices include: 1) distribution of dacitic-rhy-olitic submarine volcanic rocks of the Nishikurosawa and Onnagawa stages, 2) distribution of intrusive rocks of pre- and post-Kuroko horizon, 3) low aeromagnetic anomaly caused by hydrothermal alteration of magnetite, 4) low gravity anomaly which suggests depressions in the basement rocks such as a tectonic basin and/or caldera, and 5) nearby existence of vein type deposits. It is concluded that about 33 % of known Kuroko deposits fall within the high potential zone (score=4 and 5) that occupies only 4 % of the entire northeast Japan arc. The Kuroko potential map is, therefore, useful for limiting the target area for Kuroko type deposits in an island arc setting.  相似文献   
105.
In the last decades, landslide hazard assessment has attracted many researchers' attention. A number of parameters are suggested to be responsible to quantitatively explain the mechanism of landslides; many of these parameters are very important and factual. However, some data types and models are site-specific and could not be applied to different locations. Furthermore, the data stored in continuous parameter maps are divided into a number of classes arbitrarily, depending on the vision of the expert. Basically, this division controls the result of bivariate analysis. Besides, the responsible portion of the parameter map controlling the mechanism is also weighted arbitrarily. Based on these two facts, the class boundaries put a prejudice on the produced susceptibility/hazard maps, which result in dependence on the knowledge of the user rather than being dependent on the data and the fact itself. The aim of this study is to refine the previously defined methods in a more data-dependent trend. To achieve this goal, two new concepts: seed cells and percentile maps are introduced. Seed cells are the zones that are considered to represent the best undisturbed morphological decision rules (conditions before landslide occurs) and would be achieved by adding a buffer zone to the crown and flank areas of the landslide. To quantitatively classify the input parameter maps, the data distributions of seed cells in the parameter maps are divided into a number of classes on the basis of their distribution's percentile break-points upon which the parameter maps are directly dependent on the seed cell distributions, hence to the data itself.  相似文献   
106.
The purpose of this study is the development, application, and assessment of probability and artificial neural network methods for assessing landslide susceptibility in a chosen study area. As the basic analysis tool, a Geographic Information System (GIS) was used for spatial data management and manipulation. Landslide locations and landslide-related factors such as slope, curvature, soil texture, soil drainage, effective thickness, wood type, and wood diameter were used for analyzing landslide susceptibility. A probability method was used for calculating the rating of the relative importance of each factor class to landslide occurrence. For calculating the weight of the relative importance of each factor to landslide occurrence, an artificial neural network method was developed. Using these methods, the landslide susceptibility index (LSI) was calculated using the rating and weight, and a landslide susceptibility map was produced using the index. The results of the landslide susceptibility analysis, with and without weights, were confirmed from comparison with the landslide location data. The comparison result with weighting was better than the results without weighting. The calculated weight and rating can be used to landslide susceptibility mapping.  相似文献   
107.
This paper presents an attenuation relationship of peak ground acceleration (PGA) derived from Turkish strong motion data for rock, soil and soft soil sites and an iso-acceleration map of Turkey based on this relationship. For the purpose, among all the three-component accessible records, 221 records from 122 earthquakes that occurred in Turkey between 1976 and November 2003 were selected. The database was compiled for earthquakes with moment magnitudes (Mw) and PGA values ranging between 4.1 and 7.5, and 20 and 806 gal, and distances to epicenter considered in the database were between 5 and 100 km. From the regression analysis of the data, an attenuation equation of PGA considering rock, soil and soft soil conditions was developed. The PGA values predicted from the equation suggested in this study and those both from a few domestic equations and some imported equations were compared. In addition, an iso-acceleration map of Turkey was constructed using the suggested attenuation equation and considering both known active faults and epicenter locations of the earthquakes that have occurred in Turkey.  相似文献   
108.
从等值线图形获取DAT和GRD格式的数据文件   总被引:2,自引:0,他引:2  
王宜芳 《现代测绘》2004,27(2):45-46
在盆地模拟研究工作中,需要处理大量的地质数据和地质图件,一方面,随时需要把各种数据变为可视的图形;另一方面,还时常需要从图形中得到研究中所必需的数据,例如,由构造图得到研究区域的深度数据文件。本文介绍一种从等值线图形获取DAT格式和网格化GRD格式的数据文件的方法。  相似文献   
109.
基于分层的面状地图符号设计   总被引:3,自引:1,他引:3  
根据面状符号的结构特征和实现机制 ,提出了基于分层的面状地图符号设计方法 ,把面状符号分为若干层 ,每层采用一种填充方式 ,并在基于VC 的Cartosymbol软件中实现。结果表明 ,该方法既便于地理现象的表达 ,又便于计算机实现。  相似文献   
110.
常州市数字化测绘工程及GIS建库概述   总被引:2,自引:0,他引:2  
数字化地形图和地籍图是城市规划、建设和管理及国土资源管理的重要基础资料.也是开展数字城市和信息化建设的最基础平台。通过对系统总体结构的设计和应用成果介绍,分析了目前基础地理数据生产、管理和应用的现状,介绍了基于GIS的常州市数字化地形图、地籍图测绘工程总体目标及基础地理信息系统总体设计.并概述了整个数字化测绘工程的实施过程和特点。  相似文献   
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