Abstract

Mapping of carbonatites and related mineral deposits has occupied prominent place in mineral resource exploration programs given their potential to host valuable concentrations of critical metals such as rare earth elements and niobium. Based on spectral characteristics of most indicative minerals for these rocks, a mapping approach was developed using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. The combination of band rationing outcomes with components from the principal component analysis and minimum noise fraction techniques highlighted the targeted rocks, with the excellent prospective zone representing ∼0.2% of the total investigated area. This approach was successfully applied to the Gleibat Lafhouda complex to rapidly delineate carbonatites and iron oxide-apatite ore outcrops. Results were validated through field observations and in-situ geochemical analysis using a portable X-ray fluorescence analyzer. Field data have also served as training data to perform a supervised classification, allowing further improvement of the mapping results.

摘要

碳酸岩和相关矿床的测绘在矿产资源勘探计划中占据了重要位置，因为它们有可能拥有宝贵的关键金属浓度，例如稀土元素和铌。根据这些岩石的大多数指示性矿物的光谱特征，使用先进的星载热发射和反射辐射计 (ASTER) 数据开发了一种绘图方法。带配给结果与来自主成分分析和最小噪声分数技术的成分相结合，突出了目标岩石，极好的远景带占总调查面积的 0.2%。这种方法已成功应用于 Gleibat Lafhouda 复合体，以快速描绘碳酸盐岩和氧化铁磷灰石矿石露头。结果通过现场观测和使用便携式 X 射线荧光分析仪的原位地球化学分析得到验证。现场数据还用作训练数据来执行监督分类，从而进一步改进映射结果。