基于构造与蚀变信息的找矿方法初探   总被引：1，自引：0，他引：1  

夏福瑞  何政伟  许辉熙  薛万蓉 《测绘科学》2010,35(3):46-48

遥感图像蚀变信息的提取是遥感地质找矿的一个重要方法,地质构造信息作为一种指示信息对找矿也具有非常重要的意义。本文利用Landsat7 ETM+卫星影像数据,通过主成分分析方法和阈值分割技术对新疆叶城县麻扎一带进行了铁化及泥化蚀变信息的提取,并结合研究区线性、环形构造的特点,对研究区进行成矿预测,创新利用比值方法剔除伪信息,圈定找矿远景区。此工作方法效果明显,为今后加快地质找矿工作提供了一条可参考、行之有效的途径。  相似文献   

基于遥感的长沙市城市热岛与土地利用/覆盖变化研究   总被引：9，自引：0，他引：9  

历华  曾永年  柳钦火 《国土资源遥感》2008,19(4):47-52

基于多时相Landsat TM/ETM+影像,首先计算长沙市地表亮度温度,然后利用NDVI(归一化植被指数)、MNDWI(改进 的归一化水体指数)、NDBI(归一化建筑指数)和NDBaI(归一化裸土指数)4个指数,采用决策树分类方法对长沙市影像进行 土地利用/覆盖分类。在此基础上,对长沙市城市热岛的空间分布特征、时空演变特征以及城市热岛与土地利用/覆盖变化和各种影 响因子之间的关系进行研究。结果表明,随着长沙市城区范围的不断扩张,城市热岛范围也不断增大; 土地利用/覆盖类型的变化 会改变地表温度的空间分布,城市用地和裸地是城市热岛强度的主要贡献因素,水体和林地具有较好的降温作用。地表温度与4种 归一化指数的回归分析表明,它们之间存在明显的相关性,不同土地利用/覆盖类型的地表温度存在较大差异。  相似文献   

Sources and implications of particulate organic matter from a small tropical river—Zuari River,India     

Fernandes Dearlyn  Wu Ying  Shirodkar Prabhaker Vasant  Pradhan Umesh Kumar  Zhang Jing 《海洋学报(英文版)》2020,39(4):18-32

Transitional ecosystems,estuaries and the coastal seas,are distinctively affected by natural and anthropogenic factors.Organic matter(OM)originating from terrestrial sources is exported by rivers and forms a key component of the global biogeochemical cycles.Most previous studies focused on the bulk biochemical and anthropogenic aspects affecting these ecosystems.In the present study,we examined the sources and fate of OM entrained within suspended particulate matter(SPM)of the Zuari River and its estuary,west coast of India.Besides using amino acid(AA)enantiomers(L-and D-forms)as biomarkers,other bulk biochemical parameters viz.particulate organic carbon(POC),δ13C,particulate nitrogen(PN),δ15N and chlorophyll a were analyzed.Surprisingly no significant temporal variations were observed in the parameters analyzed;nonetheless,salinity,POC,δ13C,PN,δ15N,glutamic acid,serine,alanine,tyrosine,leucine and D-aspartic acid exhibited significant spatial variability suggesting source differentiation.The POC content displayed weak temporal variability with low values observed during the post-monsoon season attributed to inputs from mixed sources.Estuarine samples were less depleted than the riverine samples suggesting contributions from marine plankton in addition to contributions from river plankton and terrestrial C3 plants detritus.Labile OM was observed during the monsoon and post-monsoon seasons in the estuarine region.More degraded OM was noticed during the pre-monsoon season.Principal component analysis was used to ascertain the sources and factors influencing OM.Principally five factors were extracted explaining 84.52%of the total variance.The first component accounted for 27.10%of the variance suggesting the dominance of tidal influence whereas,the second component accounted for heterotrophic bacteria and their remnants associated with the particulate matter,contributing primarily to the AA pool.Based on this study we ascertained the role of the estuarine turbidity maximum(ETM)controlling the sources of POM and its implications to small tropical rivers.Thus,changes in temporal and regional settings are more likely to affect the natural biogeochemical cycles of small tropical rivers.  相似文献   

多源遥感数据空间叠合找矿效果研究     

丛利民  李国志  廖蕾  宋俊峰 《华北国土资源》2009,(4)

以内蒙西部朱拉扎嘎金矿为例,利用航空遥感ETM+数据和ASTER数据分别提取褐铁矿化蚀变异常,将提取结果与地质特征、地球化学特征对比分析,分析结果显示,两种数据源分别提取的异常分布范围不完全一致,但在朱拉扎嘎金矿区都有异常显示.野外验证,矿区普遍发育褐铁矿化蚀变.因此推断,在同一地区,利用ETM+数据和ASTER数据分别提取蚀变异常,异常同时出现的地区(叠合区)找矿的可能性大.  相似文献   

ASTER数据与ETM数据蚀变信息提取的对比研究——以巴什布拉克铀矿区油气还原蚀变分析为例   总被引：4，自引：0，他引：4  

叶发旺 《地球信息科学学报》2009,11(3):274-281

本文在深入分析巴什布拉克铀矿区油气还原蚀变岩石的光谱特征,ASTER与ETM数据对蚀变岩石光谱特征反映的差异性的基础上,提出了正反两种蚀变信息提取的思路和两种数据在不同思路下提取蚀变信息的效果对比。研究表明,利用ASTER数据与ETM数据在增强研究区三价铁信息,间接反映油气还原蚀变规律方面效果相当;而在直接增强油气还原蚀变信息方面,ASTER数据的应用效果明显好于ETM数据。增强的遥感油气还原蚀变信息对分析研究区白垩系油气还原蚀变规律和矿区外围铀矿找矿具有重要的意义。  相似文献   

Calibration of ASTER and ETM + imagery using empirical line method—A case study of north-east of Hajjah, Yemen     

Ali M. Qaid  H. T. Basavarajappa  S. Rajendran  S. A. Ashfaq  Junfeng Xu 《地球空间信息科学学报》2009,12(3):197-201

This study is aimed at using the Empirical Line Method (ELM) to eliminate atmospheric effects with respect to visible and near infrared bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) and enhanced thematic mapper plus (ETM+) data. Two targets (Amran limestone as light target and quartz-biotite-sericite-graphite schists as dark target), which were widely exposed and easy to identify in the imagery were selected. The accuracy of the atmospheric correction method was evaluated from three targets (vegetation cover, Amran limestone and Akbra shale) of the surface reflectance. Analytical spectral devices (ASD) FieldSpec3 was used to measure the spectra of target samples. ETM+ data were less influenced by the atmospheric effect when compared to ASTER data. Normalized differences vegetation indices (NDVI) displayed good results with reflectance data when compared with digital number (DN) data because it is highly sensitive to ground truth reflectance (GTR). Most of the differences observed before and after calibration of satellite images (ASTER and ETM+) were absorbed in the SWIR region.   相似文献   

Glacier Extent and Volume Change （1966-9000） on the Su-lo Mountain in Northeastern Tibetan Plateau,China   总被引：2，自引：2，他引：0  

WANG Yetang  ;HOU Shugui  ;HONG Sungmin  ;HUR Soon Do  ;LIU Yaping 《山地科学学报》2008,5(4):299-309

The topographic maps of 1：50, 000 scales, aerial photographs taken in 1966, one Landsat image taken in 1999, and SRTM data from 2000 were used to quantify the losses in area and volume of the glaciers on the Su-lo Mountain, in the northeastern Tibetan Plateau, China in the past 30 years. The total glacier area decreased from 492.9 km^2 in 1966 to 458.2 km^2 in 1999. The volume loss of the studied glaciers reached 1.4 km^3 from 1966 to 2000. This agrees with documented changes in other mountain glaciers of the whole Tibetan Plateau.  相似文献   

MODIS Terra Collection 6 fractional snow cover validation in mountainous terrain during spring snowmelt using Landsat TM and ETM+          下载免费PDF全文

Christopher J. Crawford 《水文研究》2015,29(1):128-138

Daily swath MODIS Terra Collection 6 fractional snow cover (MOD10_L2) estimates were validated with two‐day Landsat TM/ETM + snow‐covered area estimates across central Idaho and southwestern Montana, USA. Snow cover maps during spring snowmelt for 2000, 2001, 2002, 2003, 2005, 2007, and 2009 were compared between MODIS Terra and Landsat TM/ETM + using least‐squared regression. Strong spatial and temporal map agreement was found between MODIS Terra fractional snow cover and Landsat TM/ETM + snow‐covered area, although map disagreement was observed for two validation dates. High‐altitude cirrus cloud contamination during low snow conditions as well as late season transient snowfall resulted in map disagreement. MODIS Terra's spatial resolution limits retrieval of thin‐patchy snow cover, especially during partially cloudy conditions. Landsat's image acquisition frequency can introduce difficulty when discriminating between transient and resident mountain snow cover. Furthermore, transient snowfall later in the snowmelt season, which is a stochastic accumulation event that does not usually persist beyond the daily timescale, will skew decadal snow‐covered area variability if bi‐monthly climate data record development is the objective. As a quality control step, ground‐based daily snow telemetry snow‐water‐equivalent measurements can be used to verify transient snowfall events. Users of daily MODIS Terra fractional snow products should be aware that local solar illumination and sensor viewing geometry might influence fractional snow cover estimation in mountainous terrain. Cross‐sensor interoperability has been confirmed between MODIS Terra and Landsat TM/ETM + when mapping snow from the visible/infrared spectrum. This relationship is strong and supports operational multi‐sensor snow cover mapping, specifically climate data record development to expand cryosphere, climate, and hydrological science applications. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

基于IHS变换的重力异常与遥感影像融合的构造信息提取研究     

陈圣波  郭鹏举  张莹  刘焱 《世界地质》2015,34(4):1125-1130

本文以深部探测关键仪器装备野外实验与示范基地为例,利用影像融合技术进行地质构造信息的提取。在卫星遥感和重力异常数据空间配准的基础上,利用IHS数据融合方法,将重力异常与ETM+数据进行融合与分析。研究表明:一方面构造形迹在遥感图像及重力异常上的表征是存在差异性的,即其空间分布特征,另一方面通过卫星遥感在地表定位重力异常所反演的地质信息,能够为深部探测仪器装备野外实验选点提供科学的依据。  相似文献   

基于ETM数据的北衙地区找矿应用效果     

杨剑  薛廉  张景华 《物探化探计算技术》2015,(1):106-114

遥感技术能以较低的成本快速地提供更多更有效的地质异常信息,提高工作效率,降低风险[1]。在分析云南省北衙金矿远景区区域地质背景和控矿规律的基础上,通过目视解译的方法对该区的区域地质进行了解译,并对该区域进行详细的定量分析以及蚀变异常的光谱反映特征提取。从ETM影像中利用相关方法提取了与矿区有关的羟基、铁染异常信息,解译效果良好,划分了找矿远景区。  相似文献