ARC／INFO浮点数据结构及应用

ARC／INFO是极为重要的信息化处理软件，它的用户遍布全球，其数据文件的数据结构尚未公开，而这一结构又是广大从事地理信息系统工作者所希望了解的。为此本文对ARC／INFO的数据结构和其应用作了分析，对浮点数据结构(内有多边形拓扑关系)的如何应用也作了详细说明。     

ARC/INFO在城市环境分析中的应用

将GIS与环境科学相结合，运用ARC／INFO中的缓冲区分析，圈层叠绘，叠置分析等技术方法，实现了地理信息系统在城市环境分析中的应用。对长春市水体污染源进行了分析评价，得出潜水重点污染源10处，河流重点污染源8处，并分析其形成原因，提出建议，取得了较好的效果。     

ARC/INFO在流域水文分析中的应用

以吉林东部某山区小流域水文分析为例,将地理信息系统(GIS)与流域研究相结合,运用ARC/INFO的图像处理功能建立流域数字高程模型(DEM),利用其表面分析功能进行坡度、坡向、流线和流域识别等分析,实现GIS在流域水文分析中的应用。结果表明:运用ARC/INFO分析得到的流域坡度、坡向、流线及流域边界划分合理,输出结果直观美化,并在此基础上预测降水的汇流方向,效果较好。实现了对地形的三维化,提供了一种山区流域水文分析方法。     

基于ARC VIEW／INFO平台的流域GIS数据库的建立

本文阐述了应用ARC VIEW／INFO的转换、合并、分析和显示功能，对从不同来源的数字化数据，经过流域划分和数据层重新投影，建立起一个属于单一汇水流域的GIS数据库，其中包括流域及次流域、河流网、土壤、土地覆盖和植被等数字化图件。这一数据库的建立为水文模拟和防洪构筑物评价提供了坚实的基础。     

MAPGIS 6．0平台地学断面图形数据库向ARC／INFO 8.1平台的转换

对MAPGIS地学断面数据文件转换成ARC／INFO的数据文件的几种途径进行了探讨，指出了在转换大数据量过程中存在的问题和局限性，并在大量转换实验基础上，得出最优的解决方案。在数据转换时，点文件在MAPGIS平台下转换成E00格式，通过在ARC／INFO的ArcToolbox中选择工具将Interchange格式转换成Coverage格式；线和区文件在MAPGIS平台上转换为MIF文件，在ARC／INFO的ArcToolbox中选择工具将MIF格式转换成Shapefile格式。     

基于ARC/INFO与ARCVIEW中地震数据的空间分析

依托ARC/INFO平台,把湖北省近四十年所发生的地震的震中、震级及发震时间从文字记录信息转化为直观的并具有大地坐标的空间点位信息;利用平台功能强大的编辑模块和空间分析等功能对地震数据进行处理分析研究,并在此基础上结合ARCVIEW的桌面制图优点绘制基本图件完成输出与查询.该过程是湖北省区域稳定性评价的重要数据准备,同时也为湖北省地壳稳定性评价提供一个重要的评价因子.     

基于ARC/INFO的矿产资源数据库建设

数据是研究工作之本.应用GIS技术创建地学领域中各类GIS数据库,对空间数据和属性数据进行存贮、管理、查询、分析,具有传统数据处理方式所无可比拟的巨大优势,而对数据进行组织、维护,直观再现并传播地图与空间信息、属性信息之间的关系,让使用者从中受到启示并获得有关规划、管理和决策的有用信息是应用GIS的最终目的.本文将PC机上以ARC/INFO平台作为主要支持从而实现的新疆阿舍勒铜锌矿区矿产资源数据库的建设为例,较为详细地阐述和探讨了数据库结构设计、数据采集等一系列相关问题.     

基于Arc／INFO的地学信息系统的设计与开发

论文主要研究了基于GIS技术和数据融合技术的地学信息系统的开发问题。采用国际先进的硬件、软件作为开发平台，建立了一个比较完善的湖南省国土资源地学信息系统。系统功能除常规空间信息查询外，还包括缓冲区分析、叠置分析、地质成图等各种复杂的分析功能。它为湖南省国土资源地学信息管理提供了一个重要手段，为区域地质找矿提供了一种新的研究思路。     

MAPGIS 6.O平台地学断面图形数据库向ARC/INFO 8.1平台的转换

对MAPGIS地学断面数据文件转换成ARC/INFO的数据文件的几种途径进行了探讨,指出了在转换大数据量过程中存在的问题和局限性,并在大量转换实验基础上,得出最优的解决方案.在数据转换时,点文件在MAPGIS平台下转换成E00格式,通过在ARC/INFO的ArcToolbox中选择工具将Interchange格式转换成Coverage格式;线和区文件在MAPGIS平台上转换为MIF文件,在ARC/INFO的ArcToolbox中选择工具将MIF格式转换成Shapefile格式.     

Kalikorva structure and its position in the system of the northern Karelian greenstone belts: Geochemical and geochronological data

New geochemical data on volcanic rocks and the first U-Pb zircon ages for the Kalikorva structure made it possible to determine the time and conditions of their formation and constrain geodynamic models. The lower sequences of the Kalikorva structure is dominated by metatholeiites with high MgO, Cr, and Ni contents, high Mg#, and REE distribution patterns close to the mantle level. They contain rare komatiite interlayers and lenses of pyroxenites and peridotites and can be considered as products of the deep melting of mantle material. At the same time, the tholeiitic metabasalts bear island-arc signatures and are intercalated with metagraywackes and metadacites (adakites). This rock association could be formed under spreading conditions at the beginning of an island-arc regime. The upper sequence is dominated by metagraywackes and contains diverse rocks with both MORB (tholeiitic and komatiitic basalts) and island-arc (calc-alkaline andesite and dacites, subalkaline basalts, and picritic basalts) affinity, which is typical of back-arc basins. The U-Pb dating of zircons from the metadacites and detrital zircons from the metagraywackes of the Kalikorva structure yielded similar ages of 2785 ± 13 and 2766 ± 21 Ma, respectively. They coincide with the age of the late volcanic complex of the Hisovaara Group of the Hisovaara structure (2780 Ma). Both complexes include island-arc associations with subduction signatures and contain adakites, Nb-Ti basalts, and basaltic andesites. The metagraywackes and metadacites of the Chupa sequence of the Belomorian mobile belt are older than the similar rocks of the Kalikorva complex and have an age of 2870 ± 30 Ma. Ages of 2735 ± 20 Ma and 2720 ± 4 Ma were previously obtained for the metaandesites of the Kichany volcanogenic complex, which could be an even younger volcanic arc.     

Tantalum-bearing titanite: synthesis and crystal structure data

Synthetic titanite, CaTiOSiO₄, and the series of (Ca_1−x Na _x )(Ti_1−x Ta _x )OSiO₄ and Ca(Ti_1−2x Ta _x Al _x )OSiO₄ solid solutions have been prepared by ceramic methods, and their crystal structure determined by the Rietveld analysis. At ambient conditions, titanite can contain up to 20 mol% NaTaOSiO₄ or 60 mol% Ca(Al_0.5Ta_0.5)OSiO₄. These limits might differ in natural samples due to combination with substitutions involving fluorine and/or hydroxyl replacing oxygen together with vacancies at cationic sites. All cations located at the ^vii X- and ^vi Y-sites in the structures of tantalian titanite are disordered. Expansion of the <Si–O> bond from 1.618 to 1.621 Å in CaTi_0.8Ta_0.1Al_0.1OSiO₄ and CaTi_0.6Ta_0.2Al_0.2OSiO₄ to 1.644 Å in the CaTi_0.4Ta_0.3Al_0.3OSiO₄ titanite suggests the possible presence of some Al³⁺ in the tetrahedral site replacing Si⁴⁺ in the latter. All tantalian titanites crystallize in the space group A2/a. This implies that both single-site and complex double-site substitutional schemes induce P2₁/a → A2/a phase transition(s). The (Ca_1−x Na _x )(Ti_1−x Ta _x )OSiO₄ substitution scheme incorporates larger cations at both the ^vii X and ^vi Y sites, whereas the Ca(Ti_1−2x Ta _x Al _x )OSiO₄ scheme involves only ^vi Y-site (Al³⁺,Ta⁵⁺) cations with a slightly smaller “average” radius. Unit cell dimensions change insignificantly or increase incrementally with increase of average cationic radii in the (Ca_1−x Na _x )(Ti_1−x Ta _x )OSiO₄ series, and with an insignificant decrease in the ^viR _Y average cationic radii in the Ca(Ti_1−2x Ta _x Al _x )OSiO₄ series. Both Ta-doped titanite and CaTiOSiO₄ consist of distorted polyhedra with the XO₇, YO₆ coordination polyhedra and the SiO₄ tetrahedron in tantalian titanite being less distorted compared to those of the pure CaTiOSiO₄.