【作者】 蒋立军；

【导师】 梁一鸿；

【作者基本信息】 吉林大学 ， 地球化学， 2011， 博士

【摘要】 利用遥感技术进行矿产信息探测和定位一直是遥感地质方而应用的主要方面,矿化蚀变信息的提取则是首先且必须要解决的问题。蚀变信息指在有利于成矿作用发生的空间实体中的蚀变围岩(带)在遥感影像上反映出来的包含各种背景光谱信息在内的综合光谱信息,其背景光谱信息是指地质体/现象、土壤、植被等光谱信息。蚀变信息作为一个弱信息存在于遥感信息的背景中,虽然近矿围岩蚀变形成的蚀变围岩在矿物成分,颜色,地表状况等综合因素的影响下,使得在图像上的纹理与正常围岩有所不同。目前,遥感专题信息提取多采用同一研究区德单一阈值参数进行处理。事实上,不同景观区的专题信息背景特征存在一定的的差异,即具有背景空间分异性。如在不同景观区的遥感蚀变信息检测中,蚀变异常、背景与干扰因素是三个必须研究的对象。但“背景”与“干扰”复杂而且容易混淆,在实际工作中很难被完全界定清楚。因为遥感异常信息(包括异常信息提取的质量和精度)主要受控于决定地物本质特征及时空变异特征的区域性因素(区域参数)。区域参数可分为主导因子和环境因子两方面,主导因子是遥感蚀变异常的地物成因性区域参数,包括岩性、构造、岩浆热液活动的强弱(蚀变的强弱)等；环境因子是与遥感蚀变异常或地质异常相关的空间制约性区域参数,包括遥感蚀变异常或成矿岩体/岩脉所处环境空间的地形/地貌、土壤、植被、气候条件等。因此,遥感蚀变信息提取必须考虑其存在的地质、地理背景,采用相应的处理方法及量化参数对不同背景分区,以消除不同岩性(构造)、所处背景环境的影响.由于单数据源的局限性,利用遥感数据与化探数据融合提取异常信息已经成为找矿的主要手段。遥感与化探数据融合的目的是挖掘其中的综合找矿信息,为地质找矿提供史可靠的依据。遥感数据的不同波段从不同方面反应地物目标的成分、结构、构造等信息,遥感技术在预测找矿有利区段、优选找矿靶区等方面已取得明显成果。但因成矿条件的复杂性,遥感数据受成像时光照和大气条件、地面植被覆盖度、数据分辨率等因素的影响,对异常信息的提取仅可达到定性和半定量的程度,无法完全识别所提取出信息是否为有意义的的矿化信息。化探数据通过不同元素及其组合反应地表系统元素的运移及其富集规律。受复杂地质条件影响,化探数据所提取出的异常信息会忽略一些重要的低异常区或因某些因素影响而夸大一些异常区域,导致提取结果存在一定局限性和多解性。遥感和化探数据为地表地质体或地质现象物理特性和化学特性的表现,矿物或化学组分的特征光谱曲线是遥感对地球化学信息的响应。在机理上,二者存在一定的相关性。遥感与化探数据融合处理的目的在于实现二者的优势互补,提高异常信息提取的准确度,为地质找矿提供更为可靠的信息。本文选题于“中红外多/高光谱矿物填图及遥感异常信息提取技术应用研究”项目对遥感蚀变异常信息提取的原理与方法进行了深入研究,主要取得了以下成果：1.基于光谱理论和地质找矿理论,对现有的遥感蚀变异常信息常规提取原理与方法进行了系统研究与总结,仅从光谱数据出发所得的遥感蚀变信息对地质勘查与成矿预测难以保证其准确性,提出遥感蚀变异常受控于成因性区域参数和空间制约性区域参数的遥感制图理念。2.在上述理念指导下,通过大量野外工作和地质资料总结,对研究区遥感蚀变异常的成因性和空间制约性区域参数进行深入研究,确定了分区原则并提出分区标准化方法,对研究区从岩性、构造与植被覆盖度进行区域参数分区制图。3.对不同分区的遥感地质背景参数进行分析,实现了遥感异常信息分区、分级量化及专题制图表达。4.从遥感蚀变异常形成的物理机制出发,基于遥感蚀变-矿物组分关联分析,从矿物组分方面进行了遥感与地球化学数据融合研究。重点对地球化学数据和遥感数据之间的空间配准及量化对应关系研究,达到二者在空间及成因上的联系对二者进行数据融合并进行数据重建,进一步提高了遥感蚀变异常信息成因性区域参数的准确度。5.综合光谱蚀变异常、岩性构造分区、植被分区及与地球化学数据融合,对分区标准化方法进行系统研究并圈定出成矿远景区。6.主要创新点(1)提出遥感蚀变异常受控于地物成因性区域参数和空间制约性区域参数遥感制图的理念。对找矿有指导意义的蚀变信息取决于岩性、构造、岩浆热液活动等地质环境因素的同时,遥感蚀变异常或成矿岩体/岩脉所处的地形/地貌、土壤、植被、气候条件等环境空间的制约,单纯利用光谱数据进行蚀变异常提取存在一定缺陷,必须考虑异常提取的区域参数这一决定性因素。(2)提出遥感异常分区标准化方法并应用于遥感蚀变异常信息提取研究。通过岩性构造分区、植被覆盖度分区研究,对不同分区采用不同参数及方法进行遥感蚀变异常信息提取。更多还原

【Abstract】 Using remote sensing technique to detect and locate the mineral information have been the main aspect of remote sensing geology application, mineralized alteration information extraction is the first and must solved problem. Alteration information refers to synthetical spectral information including all kinds of background spectrum reflected by integrative wallrocks in the spatial entity which is benefit to the metallization taking place in the remote sensing imagery. The background spectrum refers to some environment background such as the spectrum of soil, vegetation, and etc. Altered information as a weak information exists in remote sensing information in the background. Although near-ore wall rock alteration altered rock formation different from normal wall rocks in image texture under the influence of comprehensive factors such as mineral composition, color, the surface status.At present, remote sensing thematic information extraction mainly use single threshold parameter in the same area. In fact, thematic information background characteristics have certain differences in different landscapes, mean that have background space points heterosexual. Such as altered information detection in different landscape, altered abnormalities, background and interference are three must studied factors. But background and interference are complex and confusing, it is hard to be completely clear defined in practical work. For remote sensing abnormal information (including abnormal information extraction’s quality and precision) mainly controlled by regional factors (area parameters) which decide feature’s essential characteristics and space-time change characteristics. Regional parameters can be divided into the leading factor and environmental factor. The leading factor the feature area parameters which cause the remote sensing altered abnormal features, including lithology. structure, the intensity of magmatic hydrothermal activity (altered degree), etc. Environmental factor is the space conditionality regional parameters related to remote sensing altered abnormal or geological anomalies. Including terrain/landscape, soil, vegetation and climate conditions in remote sensing altered abnormal or metallogenic rock/dikes environment space. Therefore, remote sensing altered information extraction must consider its existing geological, geographical background. Therefore, remote sensing altered information extraction must consider its existing geological, geographical background on the different background partition, in order to eliminate various lithology (structure) and the background environmental impact.Due to the limitations of single data sources, using remote sensing data and geochemical data fusion to extract anomaly information has become the main means of ore prospecting. The purpose of Remote sensing and geochemical data fusion is excavate comprehensive prospecting information, provide geological prospecting more reliable basis. Remote sensing data’s different bands reacts features’ different aspects of composition, target structure, construction and other informations. Remote sensing technology have achieved significant results in predicting favorable ore-prospecting segment, selecting the aspects of ore prospecting target area. But because of the complexity of metallogenic conditions, remote sensing data influenced by light and atmospheric conditions, ground vegetation coverage, data resolution factors, the extraction of anomaly information can be achieved only qualitative and semi-quantitative degree, cannot completely identify whether information extracted is meaningful mineralization information. Geochemical data through different elements and their combination to react the migration and enrichment regularity of surface systems element. Influenced by complex geological condition, the anomaly information extracted from geochemical data may ignore some important low abnormality area or because of certain factors and exaggerate some anomaly area. Result in the extract results have some limitations and multi-solutions. Remote sensing and geochemical data is the performance of surface geological or geological phenomenon physical properties, chemical properties, the mineral or chemical compositions’characteristic spectral is the response to geochemistry of remote sensing. They exist certain correlation in the mechanism. The purpose of remote sensing and geochemical data fusion processing is complement each other’s advantages, improve the accuracy of the anomaly information extraction, to provide geological prospecting more reliable information.This paper’s topic is intermediate infred multiple/high spectrum mineral mapping and remote sensing anomaly information extraction technology application research, do a further research to the principle and method of remote sensing altered anomaly information extraction, mainly obtain the achievement below.1. Based on spectral theory and geological prospecting theory, do a systematically research and summary to remote sensing altered anomaly information conventional extraction principle and method, found the remote sensing altered information obtain only from the spectral data is hard to precisely help the geological survey and mineralize prediction. Propose the concept that remote sensing altered abnormal formation controlled by cause area parameters and space regional parameter.2. Under the guidance of the afore-mentioned concepts, through field work and geological data summary, do further research to cause area parameters and space regional parameter in the study area, determine the partition principle and put forward partition standardization method, from the lithology, structure and vegetation coverage area parameter did partition drawings in the study area.3. Analyze different division of remote sensing geology background parameters, realized remote sensing anomaly information partition, grading quantification and thematic mapping expression.4. Start from the physical mechanism of remote sensing altered abnormal formation, based on remote sensing altered-mineral components of correlation analysis, do remote sensing and geochemical data fusion research from the mineral components aspect. Emphasis on the registration and quantization corresponding relations between the space of geochemical data and remote sensing data. Get the contacts of space and cause to do the data fusion, then reconstruction the data. To further improve the remote sensing altered anomaly information cause regional parameters accuracy.5. Comprehensive spectral altered abnormal, lithology tectonic division. vegetation partition and geochemical data fusion, systematic research the partition standardization method and delineate the mineralization vision zone.6. Main innovate points(1) Propose the concept that remote sensing altered abnormal formation controlled by cause area parameters and space regional parameter.The guiding significance for ore-prospecting altered information depends on geological environment factors such as the lithology, structure, magmatic hydrothermal activity, at the same time, constraint by Remote sensing altered abnormal or environmental space such as terrain/landscape, soil, vegetation and climate conditions which the rock/dikes lies. Simply use spectral data to extract altered anomalies exist certain defects. In abnormal extraction, must consider the decisive factor-regional parameters.(2) Propose remote sensing partition standardization method and applied to remote sensing altered anomaly information extraction research.Through the lithologic tectonic division, vegetation coverage partition research, using different parameters and method in different partition to extract remote sensing altered anomaly information.更多还原