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1.
端元提取是高光谱遥感信息提取与分析的基础,也是解决高光谱图像混合像元分解的关键.本文针对研究区高光谱遥感数据特点,进行了辐射校正、最小噪声分离变换(MNF)及纯净像元指数(PPI)处理,在此基础上,应用二维散点图和三维散点图分别提取了端元波谱,并开展了端元属性的判别研究.岩矿端元的提取与分析为后续岩矿种类识别奠定了基础,直接影响最终成果的准确度.  相似文献   

2.
蚀变遥感异常在矿产资源勘察中已经取得了很大的进步,目前利用遥感技术已经发现了多个矿(化)点。但这种方法给出的异常范围大,没有针对性。相似的矿床类型蚀变岩波谱特征相似,如果利用这个特点,在异常提取上限定矿床类型蚀变岩的波谱特征,有针对性的提取异常,从而达到分类型矿床蚀变遥感异常的识别。采用这种方法在东天山地区和东准噶尔地区取得了非常好的效果,已经发现了多个矿(化)点。  相似文献   

3.
文章以新疆西准噶尔托里金矿带为例,基于ETM数据源,在矿区矿化蚀变体系系统研究基础上,以典型岩、矿石地物波谱的差异性为依据,设计出适合本区的混合矿化蚀变信息分解-复合提取方法,通过混合蚀变信息分解、多变量蚀变信息增强、对增强图像(复合)合成3个工作环节,形成最终的蚀变信息提取图像。经对比后,有18处遥感异常为已知金矿的反映,有3处遥感异常已提供国土资源大调查使用。  相似文献   

4.
成像光谱以图谱合一、自动生成像元光谱进行直接识别岩矿而极具应用潜力.本文提出并利用基于地物完全谱形特征的成像光谱遥感多波段组合的主成分(PC,Principal Component Analysis)变换方法提取岩类与蚀变分布;相应地利用光谱角识别技术直接提取与矿有关的蚀变矿物;最终进行波段组合、波段运算、反差增强与RGB合成提取出相关岩矿信息进行成矿综合分析.利用岩矿谱形特征进行谱段组合的PC变换的第一分量(PC1)更多地包含岩矿的波谱特征;PC2噪声多,信息模糊,相对信噪比低.利用PC1提取岩矿信息可靠、准确.这是一种面向目标的定量与半定量相结合的岩矿识别技术,在后沟金矿区起到了良好的应用效果.  相似文献   

5.
王曦  程三友  林海星  陈静  肖良 《地质论评》2021,67(6):67120017-67120017
青海赛什腾地区位于无人区,穿越条件极差,传统地质找矿勘探工作难以开展,因其植被稀少,有利于多光谱遥感数据提取矿化蚀变信息。本文以Landsat8和Aster数据为数据源,利用成像光谱法以及主成分分析法对赛什腾地区进行矿化蚀变信息的提取,成像光谱法包括最小噪声变换(MNF),像元纯净指数(PPI),N维可视化端元识别(N-Dimensional Visualization)以及光谱角匹配(SAM),最终获得了赛什腾地区矿物信息分布图。利用主成分分析法对Landsat8和Aster数据分别提取黄铁矿、褐铁矿等铁染蚀变矿物和绢云母等羟基蚀变矿物,通过对Aster和Landsat8两种数据提取的蚀变信息进行空间叠加分析,定量地分析对比两种数据的蚀变信息提取效果,具有提高提取蚀变信息准确性的优势。通过样品实测光谱及镜下鉴定特征验证了研究区铁染以及羟基蚀变存在的真实性,并将矿化蚀变信息分布图与野外调查已知矿(化)点坐标进行叠加验证,结果显示矿(化)点坐标基本落在提取的矿化蚀变范围内,说明基于这两种遥感数据的处理方法以及提取结果是可靠的,为圈定找矿靶区以及扩大找矿范围提供了重要的指导意义。  相似文献   

6.
常青 《甘肃地质》1999,8(1):49-56
依据前人有关资料,初步研究总结了甘肃北山南带主要岩(矿)石反射波谱曲线特征及地质意义,探讨区内与金矿化密切相关的岩石、构造及热流蚀变带在遥感图像上的主要特征及解译标志,指出该地区TM图像彩色合成最佳波段组合模式为:TM7(红)+TM5(绿)+TM4(蓝),为进行图像功能处理和计算机提取蚀变信息等遥感技术方法的应用研究提供了依据  相似文献   

7.
在植被覆盖区,由于高植被、多水系、多阴影的影响,遥感蚀变信息提取一直未能取得良好的矿化蚀变效果。江西大浩山金矿区位于九江坳陷与江南地块九岭隆起的交界部位,区内植被覆盖稠密、水系沟壑纵横,传统的干扰信息掩膜+主成分分析方法难以有效提取相关的矿化蚀变信息。采用混合像元分解技术(SMACC,端元提取技术),通过对像元线性分解可从遥感图像中获取各个地物端元的反射亮度值及丰度信息;识别各地物端元,去除干扰端元(植被、水体等),进而对有用地物端元进行有补偿机制的遥感影像重组;最终采用主成分分析法从重组影像中有效提取矿化蚀变信息。与传统的掩膜方法相比,在植被覆盖率较高的区域,混合像元分解法避免了传统方法在掩膜干扰信息的同时消除矿化蚀变信息的弊端,取得了良好的效果;在植被覆盖率较低的区域,混合像元分解能分离去除少量植被信息,提取更为微弱的矿化蚀变信息。  相似文献   

8.
ASTER遥感数据蚀变遥感异常提取研究   总被引:14,自引:0,他引:14  
吕凤军  郝跃生  石静  王娟 《地球学报》2009,30(2):271-276
基于ETM+/TM数据提取矿化蚀变遥感异常已趋于成熟, 而利用ASTER(先进星载热发射和反射辐射仪)遥感数据提取矿化蚀变遥感异常鲜有报道。本研究利用USGS波谱数据库中典型蚀变矿物反射率数据, 重建其在ASTER数据中波谱曲线研究表明, ASTER遥感数据可以提取Mg-OH、Al-OH、CO32?和Fe3+离子(基团)信息。热液矿床的蚀变围岩通常含有上述4种离子(基团), 它们的波谱特征是蚀变遥感异常提取的理论依据。本研究利用改进“去干扰异常主分量门限技术流程”, 以河北省承德地区和太行山区为例, 上述离子(基团)信息提取结果与野外实际分布相一致, 表明利用ASTER遥感数据提取上述4种离子(基团)信息是可靠的。  相似文献   

9.
ALI 遥感数据在岩矿信息提取中的应用研究   总被引:1,自引:0,他引:1  
刘汉湖 《地质与勘探》2009,45(4):456-461
论文对研究区ALI数据进行了纯净像元提取,在此基础上,对纯净像元进行N-D散点图分析,选择出不同端元并进行归类分析,作为后期分类识别的样本.这里采用决策树方法对研究区岩矿进行识别,研究发现:样本区在MNF变换后图像上的波谱(前几个波段)可分性远远大于其在变换前图像上的波谱可分性,基于此的决策树分类方法能够识别出岩矿.  相似文献   

10.
文章以新疆西准噶尔托里金矿带为例,基于ETM数据源,在矿区矿化蚀变体系系统研究基础上,以典型岩、矿石地物波谱的差异性为依据,设计出适合本区的混合矿化蚀变信息分解-复合提取方法,通过混合蚀变信息分解、多变量蚀变信息增强、对增强图像(复合)合成3个工作环节,形成最终的蚀变信息提取图像.经对比后,有18处遥感异常为已知金矿的反映,有3处遥感异常已提供国土资源大调查使用.  相似文献   

11.
This study aims to interpret and analyze images of forest fires and to establish a standard procedure for image processing and interpretation. A forest fire in Victoria, Australia, that occurred in 2009 is used as an example. The extent of the disaster can be analyzed from Formosat-2 images and ALI data. The results show that fire distribution information can be quickly retrieved through scatter plots created by ALI’s red and short-wave infrared channels. The burn zones can be rapidly identified from a combination of these wave bands. Moreover, the process of the life of the fire can be deduced through smoke information and changes in the burn zones observed from the images. The maximum likelihood method and K-means method are adopted to rapidly determine the sizes and ranges of the burn zones. The precision obtained by applying this method to images influenced by smoke is 75.74 %, while that without the influence of smoke is 81.92 %.  相似文献   

12.
We present a numerical method and the URAN(IA) computer code for two-dimensional, axially symmetric radiative-transfer computations in molecular lines and spectral modeling. The algorithm is based on Monte Carlo computations of the mean radiation intensity and Accelerated Λ Iterations (ALI) to provide self-consistency between the radiation field and molecular excitation. The code is applied to the structure and kinematic properties of the starless core L1544, which is often considered to be the collapsing core of a molecular cloud. This object has been well studied, but none of the one-dimensional models obtained earlier has been able to provide a self-consistent picture of its structure and kinematics. We show that the spectral features of L1544 can be reproduced in a two-dimensional model in which the cloud has an axial ratio of 2: 1, a mean velocity of contraction (collapse) of Vr~50 m/s, and a rotational velocity of up to V φ ~ 200 m/s. We construct the model of L1544 based on a continuous transition from an initially homogeneous cloud to the observed configuration. The velocity of the contraction is appreciably lower than is predicted by one-dimensional dynamical models. We discuss the problems of interpreting observed molecular-line profiles and prospects for developing self-consistent models for the chemical and dynamical evolution of molecular clouds.  相似文献   

13.
Developments in information and communication technologies offer new opportunities to use and integrate scientific data that have been collected by researchers and scholars from diverse fields of inquiry. Data archives and digital repository systems are being developed to preserve current and legacy scientific data and technical information for use by others. However, capabilities are needed for data producers of various disciplines to easily and efficiently submit their data into archival systems for preservation. Analysis of digital preservation requirements has identified the requirements for services to support the submission and review of scientific data for preservation. Data submission and review processes are segmented into services, which are defined to support efficient preparation of scientific data for ingest into an archive or digital repository system. A model is proposed to inform the design of submission and workflow services for preserving interdisciplinary scientific data. Recommendations are offered for improving the design and evaluation of systems and services to prepare and preserve scientific data for new uses by interdisciplinary communities of users in the future. Improving the infrastructure that enables members of the scientific community to submit their data for archiving contributes to the scientific data stewardship and data curation capabilities needed to preserve scientific data for future generations of users.  相似文献   

14.
Ryan  Barbara  King  Rachel 《Natural Hazards》2020,104(1):171-199

This paper investigates use of inventories, or checklists of activities, as an emergency management tool to motivate preparedness action in individuals. It develops the inventory concept to provide the foundation for a more targeted approach to storm preparation communication and community engagement. It also examines the potential efficacy of alternatives to paper-based checklists, such as web or smartphone applications. Academic and grey literature was reviewed to collect activities for a storm inventory for emergency agencies to measure individual preparedness and for individuals to measure their preparation progress. The resulting master list was refined for application and tested for useability in a pilot study of semi-structured interviews in a storm-susceptible community in Queensland, Australia. Also, clustering items by type of preparedness activity reveal where strengths and weaknesses exist in individual preparedness. For instance, preparation for leaving and safety planning were shown to be the areas of weakest activity in the pilot sample, while preparation of the house for a storm was the strongest area. In addition, behaviour change literature shows potential for effective use of an inventory-based smartphone application in motivating preparation activity. Data collected by a storm preparedness smartphone application could show where a communication or engagement program for targeted communities should be focused. It is supported by health literature that identifies preferences of individuals to make progress on complex tasks in stages, the value of lists to achievement of goals and demonstrated increase in uptake of activities prompted by smartphone applications over web or paper-based diaries.

  相似文献   

15.

By means of X-ray fluorescence with synchroton radiation (XRF-SR), the contents of all 14 rare-earth elements (REEs) and that of Y were determined in 12 monazite samples from different veins in the Ilmen’ Reserve (South Urals). It was found that, in anphibole-micaceous-carbonate mineralized zones within metabasites, monazites were pronouncedly depleted in middle and, especially, in heavy rare-earth elements (HREEs) (from 0.25% and below for Sm, 0.08% or below for Gd, 0.03% for Dy, 0.01% for Er and Tm, below 0.005% for Yb, trace amounts of other odd HREEs, at a Y content of 0.1% or below). Monazites from the veins of granitic pegmatites were characterized by vastly decreased La contents (4–8 compared to 11–13% for the group above), at high values for Pr (to 3%), Nd (to 8%), Sm (to 1.3%), Gd (to 1.1%), Dy (to 0.9%), Er (to 0.2%), Yb (to 0.05%), and Y (from 0.2 to 1.7%). Here, the values for odd REEs are also quite high compared to the group above (to 0.2% for Tb, to 0.08% for Ho, and to 0.1% for Tm).

  相似文献   

16.
王莉  贺兆成  刘彩云 《山东地质》2011,(8):61-63,66
为切实维护失地农民的合法权益,日照市不断加快征地补偿安置制度改革的步伐,积极探索失地农民的保护性就业政策措施,努力拓展失地农民安置渠道,逐步建立起失地农民的社会保障制度,为失地农民安居乐业以及维护社会长治久安提供了有力保障。  相似文献   

17.
Indicator cokriging is an alternative to disjunctive kriging for estimation of spatial distributions. One way to determine which of these techniques is more accurate for estimation of spatial distributions is to apply each to a particular type of data. A procedure is developed for evaluation of disjunctive kriging and indicator cokriging for such an application. Application of this procedure to earthquake ground motion data found disjunctive kriging to be at least as accurate as indicator cokriging for estimation of spatial distributions of peak horizontal acceleration. Indicator cokriging was superior for all other types of earthquake ground motion data.  相似文献   

18.
Horizontal drains, used independently or as part of a more complex remediation scheme, are frequently installed to mitigate the effects of increased groundwater in slope stabilization projects. Due to a general trial and error approach to their design, the need for improved design practices has been recognized. The procedures established by Crenshaw and Santi in 2004 made some advances in this direction, but did not account for slopes with drains that were not horizontal or for sloping low-permeability layers underneath the slide mass. Furthermore, the method outlined by Crenshaw and Santi is time-consuming and requires some trial and error calculations to achieve convergence. Therefore, the method has been modified to account for nonhorizontal elements, and a horizontal drain spreadsheet has been developed to streamline the design for projects where horizontal drains will be installed. The horizontal drain spreadsheet may be used to: (1) predict a conservative piezometric profile in a drained slope for use in slope stability analyses, (2) predict piezometric heads in any single piezometer in a drainage field, and (3) predict drain spacing for design purposes. This document explains the revisions to Crenshaw and Santi’s procedures and provides instructions for applying the method. The instructions may be used for hand calculations, but are specifically intended for use with the horizontal drain spreadsheet. The spreadsheet may be used for slopes composed of silty or clayey sands, silts, and silty or sandy clays.  相似文献   

19.
《Chemical Geology》2007,236(3-4):247-265
A knowledge of the processes involved in streamflow generation are critical to an understanding of solute transport and weathering rates in upland catchments. The determination of specific flow pathways and the formulation of process-based models have proved difficult in such terrains, largely due to the heterogeneous nature of catchments and the necessary limitations of bulked parameter models. Natural geochemical tracers have proved invaluable in developing conceptual models of catchment functioning and for constraining weathering processes and geochemical cycling. Strontium isotopes have been used as a natural tracer to calculate weathering rates for Sr and Ca, and to constrain the dominant flow pathways in two upland forested sub-catchments (Afon Hafren and Afon Hore) of the River Severn at Plynlimon in Central Wales. The dominant source of Sr in the catchments is considered to be from the weathering of silicate minerals. Weathering rates for Sr and Ca in the Afon Hafren, calculated using Sr isotopes, were similar to those derived from mass balance studies. The rates for the Afon Hore were similar for Ca, but significantly different for Sr. The reason for the difference is unclear, but may be due to additional sources (calcite) in the catchment. Strontium isotope ratios for different input sources and compartments within the catchment were characterised and helped to identify potential flow pathways. The data suggest an important role for groundwater inputs in contrast to previous models which indicated a dominant role for soil waters.  相似文献   

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