试用主分量分析方法提取澜沧江兰坪地区铜矿化蚀变遥感信息

通过图像影像特征分析,并经地面调查证实,澜沧江兰坪地区铜矿化蚀变与围岩存在反射波谱特性差异,即在TM5(近红外)波段(1.55μm-1.75μm)蚀变岩呈高反射率。以此为依据,进行了提取与铜矿化蚀变相关的TM遥感信息的计算机图像处理技术方法研究。实践证明,该区主分量分析处理图像效果最佳。图像上显示的色调异常,通过与红土涧矿区地质勘查资料对比和根据兰坪地区图像上典型地物样区色调理论分析,评价了遥感异常的地质意义。由于图像预处理(几何校正、亮度拉伸、多元统计,最佳波段组合选择等)是针对澜沧江兰坪全区的特征进行的,故处理方法在全区内均有一定适用性。本文结合公式2、图4、表4、封二彩片5等实际材料较详细地介绍了有关提取铜矿化蚀变遥感色调异常信息的方法技术。     

矿化信息提取的混合蚀变遥感模型——以鹰嘴山金矿区为例

在围岩蚀变类型丰富、成矿作用复杂的甘肃省鹰嘴山金矿区,依据矿化蚀变岩与其围岩的波谱特征差异,通过对地面实测光 谱数据及其岩矿石多元数据的统计分析,建立混合蚀变遥感模型。选择最佳变量图像或变量图像组合,最终提取出该地区的混合蚀变 遥感异常信息。实践证明,该方法在矿化信息的提取上效果显著。     

基于主成分分析和分形模型的ASTER蚀变异常信息提取

遥感蚀变异常信息在一定程度上可以反映出围岩蚀变情况.为了利用遥感数据提取围岩蚀变异常信息,通过分析蚀变矿物的波谱曲线,首先得出其在ASTER各波段的吸收、反射特征;然后选择特征明显的波段做主成分分析,并依据其光谱特征与特征向量的对应关系,确定出主要包含围岩蚀变信息的主分量;最后对该分量用分形模型计算其异常灰度的阚值,来...     

新疆乌恰县花园铜矿遥感近矿找矿标志分析

本文利用ETM+多光谱数据,通过合成、融合、校正等数据处理获得研究区基础图像。在掩模数据处理基础之上,利用主成分分析法提取铁染、羟基矿化蚀变异常信息,并根据遥感影像进行了有关成矿控矿构造的遥感地质特征"五要素"解译。从遥感地质的角度分析了该矿床的遥感近矿找矿标志,以期为该地区找矿工作提供一定线索和依据。     

稻城地区遥感蚀变信息提取研究

根据围岩蚀变在多波段遥感图像（TM）上具有的光谱特征,利用比值分析、主成分分析及比值增强后主成分分析等方法,对 四川省稻城地区围岩蚀变信息进行提取和分析,通过多层次的筛选和评估提取矿区异常区,制作遥感异常图。     

基于ETM~+的遥感蚀变信息提取方法对比研究

为从微观到宏观了解、掌握和运用围岩蚀变的特征与原岩特征,寻找大型矿床或大型矿集区,在总结常用遥感蚀变信息提取模型的基础上,结合主成分分析(PCA)和支持向量机(SVM)算法,建立了基于“掩模处理-主成分分析-支持向量机( MASK - PCA - SVM,MPs)”的遥感蚀变信息提取模型.在新疆哈图地区进行的基于ETM+的不同蚀变信息提取模型应用对比研究表明,使用常用模型提取出的蚀变信息和矿点吻合效果较差,而基于MPS模型提取出的蚀变信息与已知矿点的吻合率可达86.51％;结合地质专家知识、地质图和一个已知异常点的分析结果表明,基于MPS模型的蚀变信息提取精度较高,在研究区地质应用中效果较好,为今后该区的遥感蚀变信息提取工作提供了一种新思路.     

内蒙古锡林郭勒盟布鲁特地区遥感矿化信息提取及应用

选用美国陆地卫星Landsat-7的ETM+数据,进行遥感蚀变信息提取方法实验研究,利用掩膜技术和去植被等综合预处理后,采用PCA和比值图像处理方法,提取了内蒙古锡林郭勒盟布鲁特地区遥感矿化蚀变信息,结合区域地质背景与成矿条件,进行试验区的成矿预测与靶区圈定,取得了很好的实际应用效果。在信息提取图像上,含羟基矿物岩石主要呈蓝色,影像上呈现绿色的区域则为同时包含羟基和铁染信息的区域。在遥感影像上不同岩性地层和线性构造也有突出显示。因此,利用ETM+遥感数据,采用多种不同的方法进行对比研究,能够提高遥感矿化蚀变提取的准确度,并对今后在遥感找矿工作中具有一定的指示意义。     

基于ASTER数据的江拉昂宗铜多金属矿床矿化蚀变信息提取与分析

以西藏冈底斯成矿带中段江拉昂宗矽卡岩型铜多金属矿床作为研究区,基于ASTER遥感数据的多波段优势,应用比值法,对该矿区进行大理岩化、绿帘石化和透辉石化矿化信息的蚀变提取。在此基础上,建立蚀变对于成矿影响程度的判断,提高了遥感矿化蚀变信息识别精度。此方法应用性强,充分体现了此矿区及其外围蚀变规律,为江拉昂宗外围找矿提供了可靠依据。     

云南播卡金矿遥感蚀变信息提取及成矿预测

云南东川播卡金矿位于康滇地轴中段东缘,成矿背景复杂,找矿潜力巨大.利用ETM+遥感影像对研究区进行构造解译和矿化蚀变信息提取,并结合区域地质和物化探异常信息进行综合找矿信息分析.研究结果表明,该矿区南北向构造与东西向构造交叉部位附近蚀变异常信息强烈,在区内呈规律性变化,播卡金矿的南部与研究区东部的南北向蚀变带找矿前景良...     

青海芒崖地区岩石光谱特征分析及应用

在对青海芒崖金多金属成矿区地表岩石光谱测试和分析的基础上,研究了该区与金多金属矿化有关的蚀变岩及围岩的光谱特征,以及在对应TM波段上的光谱差异性,据此,建立了矿化蚀变遥感信息定量提取模型,并利用TM图像定量提取矿化蚀变信息.     

阿克苏河-塔里木河水系水质污染遥感监测与评价

 采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的 污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体 污染变化曲线,得出污染物浓度随着远离上游而增加。     

Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data

The hard-rock hilly Aravalli terrain of Rajasthan province of India suffers with frequent drought due to poor and delayed monsoon, abnormally high summer-temperature and insufficient water resources. In the present study, detailed analysis of meteorological and hydrological data of the Aravalli region has been carried out for the years 1984–2003. Standardised Precipitation Index (SPI) has been used to quantify the precipitation deficit. Standardised Water-Level Index (SWI) has been developed to assess ground-water recharge-deficit. Vegetative drought indices like Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) and Vegetation Health Index (VHI) have been computed using NDVI values obtained from Global Vegetation Index (GVI) and thermal channel data of NOAA AVHRR satellite. Detailed analyses of spatial and temporal drought dynamics during monsoon and non-monsoon seasons have been carried out through drought index maps generated in Geographic Information Systems (GIS) environment. Analysis and interpretation of these maps reveal that negative SPI anomalies not always correspond to drought. In the Aravalli region, aquifer-stress shifts its position time to time, and in certain pockets it is more frequent. In comparison to hydrological stress, vegetative stress in the Aravalli region is found to be slower to begin but quicker to withdraw.     

Landslide risk analysis between Giri and Tons Rivers in Himachal Himalaya (India)

The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies.     

Gravity Changes Before Large Earthquakes in China: 1998-2005

Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 200...     

GNSS系统及其技术的发展研究

阐述了国际上卫星导航系统的总体发展,对美、俄、欧、中的四大全球系统,以及相关的区域系统和增强系统进行了简单的介绍,研究分析了GNSS系统及其技术的发展趋势,同时分析了我国Compass全球系统面临的机遇和挑战,并提出了我国未来工作的建议.     

“4D”技术及其应用

介绍“４Ｄ”（即数字地面模型、数字正射影像、数字栅格地图和数字线划地图）系列产品的生产流程、关键技术、及其在耕地保护、防灾减灾救灾和城市规划等方面的应用方法。     

Virtual Australia: its key elements – know,think, communicate

Abstract

Virtual Australia is not a well-defined or agreed concept. This discussion paper conceptualises Virtual Australia as a ‘virtual [digital] model containing and representing all non-trivial objects and their contextual environment – from blue sky to bedrock – in real world Australia’. It describes a scenario for Virtual Australia, one or two decades from now, in which the locations and conditions of non-trivial objects and their environment are updated automatically through a combination of remote sensing and wireless communication technologies in support of a ‘Supranet’. It then examines the concept of the ‘Supranet’ – a pervasive information network based largely on wireless technology linking the physical world to a virtual model in real time – and develops and discusses three principal characteristics of the Supranet: the ability to have or collect specific information (know); the ability to process information (think); and the ability to communicate that information. If, in the near future, any or all non-trivial devices are to some extent able to know, think and communicate, the potential for object autonomy will be realised.     

Toward seamless indoor-outdoor applications: Developing stakeholder-oriented location-based services

Location-Based Services (LBS),an emerging new business based on smartphone and mobile networks,are becoming more and more popular.Most of these LBSs,however,only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role.Our specific aim is to solve these issues.This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders.     

GIS空间数据的采集误差及其分析

本文详细阐述了GIS数据采集过程中的误差来源，重点分析了通过地图、遥感和摄影测量等方式采集数据所产生的误差及其特性，分析了其对GIS数据的影响与消减方法。     

地理数据库的关系模型及其实现

本文从以图论观点分析地理实体入手,系统阐述了地理数据库关系模型的设计法和过程。作者于1984年4～9月间在微型机上设计建立了关系型地理数据库的实方验系统(RGDB)。该系统采用了本文提出的关系模型,采用了可动态扩库的子库组合结构,这种结构具有灵活性和提高空间利用率的优点。RGDB含有多种功能的数据操作命令,除了具有一般检索功能外,还能进行“开窗”选取和十分“自由”的映象选取。本文对RGDB系统的主要性能和实现途径作了扼要介绍。