应用遥感图像进行宝成铁路沿线地质灾害的分析

本文通过对4400多张不同时期航片和5幅卫片(部分用计算机和光学图像处理等技术进行了 信息增强提取)的解译, 结合前人资料和地面调查验证, 对宝成铁路(宝鸡-绵阳段)沿线约 5000km²范围的灾害地质现象和环境地质因素进行了分析, 论述了地质灾害的分布发育规律及与地 质环境的相互关系, 提出了铁路沿线地质灾害的防治对策和建议。     

成像光谱岩矿识别方法技术研究和影响因素分析

在遥感地质应用中 ,岩矿光谱和空间分布的精细特征是空间与光谱高分辨率遥感的优势所在。随着传感器性能的提高 ,尤其是光谱分辨率的提高 ,大为改善了岩矿信息识别与提取的技术环境。但是 ,由于高光谱分辨率的成像光谱波段带宽很窄 ,在岩矿光谱信息遥感、识别与提取的过程中岩矿信息极易受诸多因素的制约和影响。本文围绕在岩矿光谱信息的获取、光谱特征信息识别与提取的过程中 ,分析与岩矿光谱特征信息息息相关的组成成分、内部结构与构造 ,以及与之发生相互作用的外部环境或过程 ;通过理论、模型、模拟和试验测试分析相结合的方法 ,开展分…     

国产高分遥感技术在矿山环境调查中的应用分析

采用高分卫星数据对鄂西某磷矿开采集中区开展矿山地质环境要素调查,通过提取矿山环境专题信息,分析调查区内地质灾害集中程度与矿山周边环境,结果表明区内尾矿库、露天采场及周边区域是地质灾害的高发区域,高分技术对矿山地质环境调查拥有巨大应用潜力,对构建"和谐矿区,和谐社会",预防矿山环境地质危害及实施矿业可持续发展战略具有十分重要的理论意义和实用价值。     

地质资料信息集群化共享服务平台关键技术研究

地质资料是地质工作形成的重要基础信息资源,是国民经济和社会发展的重要信息支撑。国土资源部非常重视地质资料的开发利用和共享服务,将地质资料信息集群化产业化列为部重点工作之一。但是,地质资料分散保管、服务的现状为全国统一集群化服务的实现出了一道难题,现有的数据集中服务方式难以实现,为此,本文在深入调研和技术研究的基础上,提出了“数据分散存储、服务逻辑统一”的分布式地质资料集群化共享服务构架,攻克了分布式协同的技术难题,成功实现了地质资料信息的集群化服务。这套技术可以扩展到其它分布式存储管理的各类国土资源数据领域,将有效提升国土资源信息集群化服务能力。     

地质资料信息集群化共享服务平台构架设计

地质资料是地质工作形成的重要基础信息资源,是国民经济和社会发展的重要信息支撑。提升地质资料信息资源服务能力、充分发挥其在经济社会发展中的重要作用,是当前地质工作的重要任务。国土资源部将地质资料信息集群化产业化服务列为当前重点工作之一,提出开展地质资料信息集群化共享服务平台建设。本文在对地质资料数据情况和服务现状调研基础上,对地质资料信息集群化共享服务平台建设思路、构架和关键技术进行研究,提出了内外网服务相结合的平台总体构架设计。该设计基于服务集成的思想,有效解决了数据物理分布环境下,地质资料信息服务逻辑集中服务的问题,满足了地质资料信息集群化共享服务的需求,同时也对其他类似项目有重要参考意义。     

X光支气管影象的计算机处理

本文利用计算机图象处理技术,对X光支气管影象进行处理。用可变加权窗口法,去除X光片的非支气管杂乱噪声干扰;用分段线性拉伸,对数变换法对支气管主枝、分枝进行增强;用多角边缘检测法提取支气管边缘信息图象以显示支气管分布的立体感,为支气管病变的X光诊断提供一种新方法。     

鲜水河活动断裂带TM图像中雪及其影响的抑制

在利用TM图像研究鲜水河活动断裂带时首先遇到的问题是:大片的积雪在TM图像中经常出现,干扰了图像中有用的地学信息的解译。本文主要探讨利用数字图像处理技术抑制雪等干扰信息的几种有效方法,在鲜水河地区使用这些方法增强了活动断裂带信息,获得了一些新的地质认识。     

多源地学信息数字图像综合技术及在盛源盆地的应用研究

通过图像显示系统,实现了铀资源多种地学信息数字图像的综合处理,其内容包括资料的输入 处理、资料配准和插值处理以及多源地学信息的增强、分解、提取、分类、叠合、复合等处理。 以盛源盆地为样区进行了试验性研究。利用图像的信息增强、叠合技术,研究了试验区的地质 构造环境；利用图像信息的分解、叠合技术,分析了铀、针、钾的分布格局及其地质意义；通过 矿床找矿判据的复合、提取,进行了找矿靶区的初选；来用信息的分类技术,进行了盛源盆地地区铀 资源的总体评价。通过上述计算机信息处理技术,对这个研究程度较高的老矿区,在某些重要地 质问题上,取得了一些新认识,并经野外检验,预测了六片成矿远景地段。 在上述研究基础上,初步建立了铀资源多种地学信息数字图像综合技术系统。     

掩模图像生成时阈值取值的合理性探讨

阈值取值是否合理对生成符合某种条件的二值及多值掩模图像是否正确至关重要,而这项技术是去除干扰信息及提取有用信息的关键步骤。基于不同的阈值,探讨如何判断在生成单一干扰因素的二值掩模图像时阈值是否合理的方法;并以青海省天峻地区TM数据为例,利用阈值合理的多值掩模图像得到无干扰信息的遥感图像,进而提取了矿化蚀变异常信息,以实现阈值的合理性验证。结果表明,当利用多种干扰因素的二值及多值掩模图像提取的非干扰区域一致时,则说明生成单一干扰因素的二值掩模图像的阈值取值合理,各种干扰因素相互不重叠;利用合理正确的多值掩模图像才能更有效地剔除干扰及假异常信息,提取出真实可靠的矿化蚀变异常信息;由于合理的阈值较多,应结合多种地学资料才能获得最优阈值。     

隐伏煤田的TM信息提取及地质效果

在遥感图像上,被巨厚第四系冲积层覆盖的煤田区隐伏地质构造和火成岩分布信息是一种非直接的、微弱的隐伏信息,本文以淮北煤田为实例,探讨了从TM图像上提取这种信息的可行性与方法,并分析了其地质效果。     

浙江武义萤石矿床遥感找矿预测

在分析了武义地区构造、岩性、地球化学和现有萤石矿床蚀变类型和编制出１：５００００遥感解译地质图基础之上，提出本区的萤石控矿因素及遥感找矿标志，建立遥感找矿模型。用主成分分析方法提取与萤石矿化密切相关的硅化、高岭土化蚀变信息，用“证据权重模型”法进行区域找矿预测；找到了断裂硅化蚀变带。     

基岩裸露区蚀变岩遥感信息的提取方法

笔者利用与金属矿化相关的蚀变岩的TM多波段图像像元亮度值曲线的双峰特性(TM3和TM5为高值),以柳沟峡地区为样区,进行了提取蚀变岩遥感信息的方法研究,改进了Crosta信息提取方法,认为用TM1+TM2、TM4/TM3、TM5、TM7组合进行主分量分析所获得的蚀变岩遥感异常图效果最佳。将该方法用于北祁连山西段,疏勒河以东9000km2区域内蚀变岩遥感信息提取,其结果是：在103处已知矿产地中的86处有蚀变岩遥感异常信息显示,符合率达83.5%,进而预测了找矿靶区115处。     

中巴资源卫星的矿化蚀变信息提取研究——以东天山沁城地区为例

本文利用东天山荒漠地区中巴资源卫星数据,通过掩膜处理,包括光谱角降低冲击物影响,动态阈值降低植被干扰,并对生成的基础图像用主成分分析法提取羟基异常,以标准离差σ作为遥感异常切割尺度进行异常分级。以前期ETM提取结果及东天山矿产地质图为检验源,经过对比分析,验证中巴资源卫星数据在找矿方面具有可行性。(重新修改了摘要)     

Extraction of Alteration Mineral Information from Moderate Remote Sensing Images Using MPS Method

Although alteration minerals related to metallogenesis is very important in mineral exploration, information of alteration mineral is weakly expressed in remote sensing imagery, which is often subject to interfering noise and sometimes limited in spectral and spatial resolutions. Because of easy access, moderate images are the main sources of alteration mineral information. Therefore, it is very important to develop alteration mineral information extraction methods from remote sensing images. In this paper, a combined method based on Mask, principal component analysis (PCA) and support vector machine method (SVM) was used to extract alteration mineral information from Enhanced thematic mapper plus remote sensing data with limited spectral and spatial resolutions. First, a mask image of the remote sensing imagery was created to remove interference information such as vegetation, shadow and water. Then, PCA was employed to collect sample data relating to iron, argillic, and carbonatization alteration. Finally, SVM was used to deal with alteration anomaly and build a feature extraction model of high accuracy. The Mask-PCA-SVM model is used to extract alteration mineral information from remote sensing images of Hatu area, Xinjiang Uygur Autonomous Regions, China. The results show that the new methods proposed in this paper can coincide well with known deposits occurrences, rate reached 86.51%. While, the consistent rate with known deposits of the ratio model, PCA model and Spectral angle mapper model were only 3.37, 65.08 and 69.05% respectively. This suggests that the proposed model can find the actual distribution of mineral deposits more effectively by reducing interference to a greater degree.     

Automated lithological mapping by integrating spectral enhancement techniques and machine learning algorithms using AVIRIS-NG hyperspectral data in Gold-bearing granite-greenstone rocks in Hutti,India

In this study, we proposed an automated lithological mapping approach by using spectral enhancement techniques and Machine Learning Algorithms (MLAs) using Airborne Visible Infrared Imaging Spectroradiometer-Next Generation (AVIRIS-NG) hyperspectral data in the greenstone belt of the Hutti area, India. We integrated spectral enhancement techniques such as Principal Component Analysis (PCA) and Independent Component Analysis (ICA) transformation and different MLAs for an accurate mapping of rock types. A conjugate utilization of conventional geological map and spectral enhancement products derived from ASTER data were used for the preparation of a high-resolution reference lithology map. Feature selection and extraction methods were applied on the AVIRIS-NG data to derive different input dataset such as (a) all spectral bands, (b) shortwave infrared bands, (c) Joint Mutual Information Maximization (JMIM) based optimum bands, and (d) optimum bands using PCA, to choose optimum input dataset for automated lithological mapping. The comparative analysis of different MLAs shows that the Support Vector Machine (SVM) outperforms other Machine Learning (ML) models. The SVM achieved an Overall Accuracy (OA) and Kappa Coefficient (k) of 85.48% and 0.83, respectively, using JMIM based optimum bands. The JMIM based optimum bands were more suitable than other input datasets to classify most of the lithological units (i.e. metabasalt, amphibolite, granite, acidic intrusive and migmatite) within the study area . The sensitivity analysis performed in this study illustrates that the SVM is less sensitive to the number of samples and mislabeling in the model training than other MLAs. The obtained high-resolution classified map with accurate litho-contacts of amphibolite, metabasalt, and granite can be coupled with an alteration map of the area for targeting the potential zone of gold mineralization.     

结合PCA、多尺度分割及SVM的ASTER遥感蚀变信息提取

为了利用遥感影像进行更加精确的找矿预测,本文选择新疆东天山尾亚地区ASTER数据进行矿化蚀变信息提取方法研究。为了提高信息提取精度,本文提出了结合主成分分析(PCA)、多尺度分割和支持向量机(SVM)的遥感矿化蚀变信息提取方法。首先,分析ASTER数据的特征,选取各矿化蚀变信息的特征波段,对组合波段进行主成分分析,获得主分量图像;然后,对各主分量图像进行多尺度分割,并获得分割之后的均值图像;接着,提取训练样本,利用SVM对训练样本进行训练,采用试验方法求得最优核参数和松弛变量,构造最优SVM模型;最后,运用最优SVM模型完成矿化蚀变信息的提取。进行主成分分析时,铁染蚀变信息选择Band1、2、3、4组合,Al-OH基团蚀变信息选择Band 1、4、6、7组合,OH和CO32-基团蚀变信息采用Band 1、2、8、9组合。在运行SVM时采用了序列最小优化算法(SMO)进行求解,速度提高了12%。实验结果表明,与波段比值法、主成分分析法及基于光谱角和SVM的方法等3种方法相比,本文方法提取铁染蚀变信息、Al-OH基团蚀变信息及OH和CO32-基团蚀变信息的总体精度可达到87.98%、 90.01%及88.93%,Kappa系数分别为0.8011、0.8134及0.8023,与成矿区带、已知矿点和已有不同地质背景成矿特征相关性较好。     

Use of Principal Component Analysis (PCA) of Remote Sensing Images in Wetland Change Detection on the Kafue Flats,Zambia

Abstract

The paper describes the use of Principal Component Analysis (PCA) of remote sensing images as a method of change detection for the Kafue Flats, an inland wetland system in southern Zambia. The wetland is under human and natural pressures but is also an important wildlife habitat. A combination of Landsat MSS and TM images were used. The images used were from 24 September 1984 (MSS), 3 September 1988 (MSS), 12 September 1991 (TM) and 20 September 1994 (TM). They were geometrically co‐registered and, in the process, the 80m resolution MSS images were resampled to 30m using nearest neighbour resampling. Preliminary PCA revealed that for the MSS images most of the data variance was in near infrared reflectance while for the TM images it was in mid and thermal infrared bands. Holding sensor type constant, separate inter‐band correlation analysis for each image could indicate whether the wetland was drier or wetter on one date versus another. The 1994 image was made the reference image and equivalent green, red and near infrared bands from the other images were radiometrically normalised with those on the reference image. All the bands, three from each date, were then merged into a twelve‐band image on which PCA for change detection was undertaken. A colour composite of eigen images from the resulting principal components was used in change detection. Hydrological data, indicating long‐term reduced inflow of water into the wetland due to human regulation, help explain some of the wetland change detected. Compared to a classification comparison approach to change detection for this area, PCA was found to be very useful in indicating where change had occurred, though interpretation of the changes was difficult without reference to the input images. The methodology appears to have potential use in habitat monitoring for this wetland area.     

Mapping forest leaf area index using reflectance and textural information derived from WorldView-2 imagery in a mixed natural forest area in Florida,US

The leaf area index (LAI) of plant canopies is an important structural parameter that controls energy, water, and gas exchanges of plant ecosystems. Remote sensing techniques may offer an alternative for measuring and mapping forest LAI at a landscape scale. Given the characteristics of high spatial/spectral resolution of the WorldView-2 (WV2) sensor, it is of significance that the textural information extracted from WV2 multispectral (MS) bands will be first time used in estimating and mapping forest LAI. In this study, LAI mapping accuracies would be compared from (a) spatial resolutions between 2-m WV2 MS data and 30-m Landsat TM imagery, (b) the nature of variables between spectrum-based features and texture-based features, and (c) sensors between TM and WV2. Therefore spectral/textural features (SFs) were first selected and tested; then a canonical correlation analysis was performed with different data sets of SFs and LAI measurement; and finally linear regression models were used to predict and map forest LAI with canonical variables calculated from image data. The experimental results demonstrate that for estimating and mapping forest LAI, (i) using high resolution data (WV2) is better than using relatively low resolution data (TM); (ii) extracted from the same WV2 data, texture-based features have higher capability than that of spectrum-based features; (iii) a combination of spectrum-based features with texture-based features could lead to even higher accuracy of mapping forest LAI than their either one separately; and (iv) WV2 sensor outperforms TM sensor significantly. However, we need to address the possible overfitting phenomenon that might be brought in by using more input variables to develop models. In addition, the experimental results also indicate that the red-edge band in WV2 was the worst on estimating LAI among WV2 MS bands and the WV2 MS bands in the visible range had a much higher correlation with ground measured LAI than that red-edge and NIR bands did.     

SAR和TM图像主成分变换融合中不同主分量替换的比较

常用的主成分变换融合方法是将一种遥感图像数据代替主成分变换后的第一主成分并进行反变换,从而得到融合信息的方法。但是,信息量较高的第一主成分被替换,往往造成一定的信息损失。本文对TM2、TM3、TM4、TM5和TM7进行主成分变换,然后用RadarsatSAR影像分别替换各主成分,并对其进行反变换。研究表明,与替换第一主成分或原始图像相比,替换第四和第五主成分的结果在信息量上有很大提高,且信息增强,类别间分离度增大,分类精度提高。但是,替换第四、第五主成分的融合结果相差不大.     

Landsat-8 OLI遥感数据的矿化蚀变信息提取——以重庆市彭水县为例

利用重庆市彭水县Landsat-8 OLI遥感数据和ERDAS-9.3软件进行一系列的图像增强及几何校正处理,对波段进行相关性分析,按照波段特征,选取OLI7、OLI5、OLI4波段作为基础信息源。应用图像的掩膜技术,除去植被信息的干扰,并结合典型的蚀变矿物光谱特征,运用主成分分析方法提取该区域的矿化蚀变信息,主要为铁染及羟基蚀变信息。分析表明,区域已开采矿产资源的分布情况与结果吻合,为后续的区域找矿工作提供了可靠方向。