柳园—方山口地区航空高光谱遥感固体矿产探测及找矿效果

摘要

高光谱遥感技术找矿应用是当前遥感地质领域研究的前缘和热点,国内外都在积极进行探索.本文依托国土资源部航空物探遥感中心高光谱遥感地质找矿项目,利用核工业北京地质研究院遥感信息与图像分析技术国家级重点实验室拥有的国内唯一一台CASI/SASI/TASI航空高光谱成像系统,在甘肃北山柳园—方山口地区,共采集了3500km2的高空间分辨率的高光谱遥感数据.经数据预处理,光谱重建和蚀变矿物填图,开展了航空高光谱遥感固体矿产的探测研究.从航空高光谱遥感的新角度,研究了柳园—方山口地区的区域成矿背景,构建了研究区成矿构造格架(非构造格架),提出黑石山—花牛山深大断裂带为柳园—方山口地区的区域控矿断裂,其呈EW向区段为该区最佳找矿地段的新认识.探讨了固体矿产高光谱遥感矿床定位模型的建模思路、方法,构建了研究区金属矿产的矿床定位系列模型.强调模式找矿是高光谱遥感找矿的有效途径,在研究区开展了模式找矿的示范应用,发现了7处找矿靶区,取得了明显的找矿效果.实践表明,高光谱遥感技术在地质找矿中有其独特的优势,主要是可快速、大面积地提取蚀变矿物,特别是航空高光谱遥感技术,由于可以获得高空间分辨率(可达亚米级)的高光谱遥感数据,从而可以识别规模小的近矿围岩蚀变,找矿实际上就是找近矿围岩蚀变,从这层意义上讲,航空高光谱遥感技术具有直接找矿的效果.航空高光谱遥感的快速、大面积地提取蚀变矿物的技术优势是迄今为止其他地质勘查方法无法替代的.因此,在地质找矿中应充分发挥高光谱遥感技术的重要作用.%Using Hyper-Spectral Remote Sensing (HSRS) to explore ore deposits is the frontier and hot topic in current geoscientific study,and has attracted numerous attentions.Financially supported by Aero Geophysical Exploration and Remote Sensing Center of Land and Resource and the Geological Bureau of China Uranium Industry,we obtained airborne hyper-spectral remote sensing data for the LiuyuanFangshankou area with a total area of 3500km2 using the CASI/SASI/TASI imaging spectrometer provided by the National Key Laboratory of Science and Technology on Remote Sensing Information and Image Analysis.Through data re-processing,spectra reconstructing and alteration mapping,this study carried out HSRS's research on solid mineral ores.In terms of the HSRS,authors analyzed the regional metallogenic setting of the Liuyuan-Fangkoushan area,established regional structural framework,and proposed regional ore-controlling faulting in this area.The new recognition is that the EW-trending section of the faulting should be the priority area for ore prospecting.We also discussed and established a series of the HSRS models to precisely determine the positions of ore deposits.Applying the HSRS model to guide prospecting will be an effective approach,he method was successfully used in the Liuyun-Fangshankou area,and several prospecting models have been established for the two areas above.Application of these models has made distinct ore-finding results and seven prospects have been identified in these two areas.Our study shows that the HSRS technology has unique advantages in geological ore prospect and can rapidly extract a large amount of alteration mineral data,especially,high-resolution HSRS data which can identify the nearly mineralized alteration of wall rocks.HSRS's technological advantage of high spatial and spectral resolution to extract altered mineral data is so far irreplaceable by other prospecting approaches.Therefore,HSRS should fully exert its leading role in ore exploration.