Hyperspectral sensing in support of northern mineral exploration

对魁北克北部Ni-Cu-(PGE)镁铁质-超镁铁质拉格兰带的地质样品实验室数据和航空高光谱图像(AISA和SEBASS)进行了综合研究。航空高保真成像光谱分析在技术上已经成熟，但从数据中提取地质信息所需的理论和算法仍处于早期发展阶段。很少有成像光谱仪的研究表明，在存在广泛的岩石结壳地衣涂层的情况下进行岩性测绘。计划中的研究将涉及三个基本科学问题：1)岩石结壳地衣(0.4-20微米)的光谱特征及其在掩盖基岩基质矿物学中的作用；2)从光谱成像中检测和区分镁铁质-超镁铁质岩石(纯橄榄岩、橄榄岩、辉石岩、辉长岩、玄武岩)；以及3)矿化容矿岩石的潜在圈定。将岩石样品的光谱特征与其变质矿物学联系起来，将是开发用于从航空图像绘制矿物和岩性单位的光谱探测方法的关键。镁铁质和超镁铁质岩石在矿物学上的内在相似性可能导致岩石单元之间的光谱对比度较低。因此，从图像中建立基岩类型、地衣丰度和地衣种类组合之间的联系可能会提高岩性识别能力。本提案中概述的研究涉及在加拿大北部经营的矿业公司需要详细的岩性和矿物测绘信息，以支持勘探活动。这项建议中列出的高素质人员将包括一名博士后研究员和一名研究生。

An integrated study of laboratory data from geological samples and airborne hyperspectral imagery from two imaging systems (AISA and SEBASS) is proposed for the Ni-Cu-(PGE) mafic-ultramafic Raglan belt of northern Quebec. Airborne high fidelity imaging spectrometry has come of age technologically, but the theories and algorithms required to extract geological information from the data remains in the early stages of development. Rarely have studies with imaging spectrometers demonstrated lithologic mapping in the presence of extensive rock encrusting lichen coatings. The planned research will address three fundamental scientific issues: 1) the spectral characterization of rock encrusting lichens (0.4-20 um) and their role in masking the mineralogy of the bedrock substrate, 2) the potential detection and discrimination of mafic-ultramafic rocks (dunite, peridotite, pyroxenite, gabbro, basalt) from spectral imaging, and 3) the potential delineation of mineralized host rocks. Linking the spectral characteristics of rock samples to their metamorphic mineralogy will be key to the development of spectral detection methods used for mapping minerals and lithologic units from airborne imagery. The inherent similarity in mineralogy between mafic and ultramafic rocks could result in low spectral contrast between rock units. Thus, establishing links between bedrock type, lichen abundance and lichen species assemblages from imagery may lead to an enhanced lithologic discrimination capability. The research outlined in this proposal addresses needs of mining companies operating in northern Canada for detailed lithologic and mineral mapping information in support of exploration activities. The highly qualified personnel listed in this proposal will include a post-doctoral fellow and one graduate student.