(1. 中南大學(xué) 有色金屬成礦預(yù)測教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083；
2. 中南大學(xué) 地球科學(xué)與信息物理學(xué)院，長沙 410083；3. 青海省地質(zhì)調(diào)查院，西寧 810012；
4. 湖南有色金屬控股集團(tuán)有限公司 礦山管理部，長沙 410015；5. 河南大學(xué) 環(huán)境與規(guī)劃學(xué)院，開封 475001)
摘 要: 褐鐵礦所形成的鐵帽是尋找鋁土礦的重要標(biāo)志。在分析鋁土礦地質(zhì)特征、光譜特征和遙感影像特征的基礎(chǔ)上，引入獨(dú)立分量分析(ICA)法用于鋁土礦的蝕變信息遙感提取，并與傳統(tǒng)的主成分分析(PCA)法和比值法進(jìn)行了比較。結(jié)果表明：3種方法的準(zhǔn)確率分別為84.5%、80.9%和79.4%，并且獨(dú)立分量分析的第一分量IC1的值越低，鋁土礦的蝕變程度越高，信息提取的準(zhǔn)確率也越高。遙感提取的鋁土礦蝕變面積約210.1 km2，可劃分為3個(gè)區(qū)帶，主要分布于海拔250 m以上且切割相對較大的山頂和斜坡上，而低海拔的平緩地帶鋁土礦基本不發(fā)育。初步查明了區(qū)內(nèi)鋁土礦的地表分布規(guī)律，為進(jìn)一步的找礦勘查工作提供有效的指示信息。
關(guān)鍵字: 鋁土礦；蝕變；獨(dú)立分量；信息提取；成礦預(yù)測
remote sensing data based on independent component analysis
（1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China;
3. Qinghai Institute of Geological Survey, Xining 810012, China;
4. Department of Mineral Resources, Hunan Nonferrous Metals Holding Group Co., Ltd., Changsha 410015, China;
5. College of Environment and Planning, Henan University, Kaifeng 475001, China）
Abstract:Iron cap formed from limonite is an important prospecting symbol of bauxite in the studied area. Based on the feature analyses of geological, spectral and remote sensing images, independent component analysis (ICA) was used to extract the alteration information of bauxite. The traditional methods of the principal component analysis (PCA) and ratio were compared with ICA. The test results show that the extraction accuracies of ICA, PCA and ratio are 84.5%, 80.9% and 79.4%, respectively. The lower the value of the first component of ICA is, the higher the degree of bauxite alteration and the extraction accuracy are. The surface area of bauxite alteration extracted from IC1 is about 210.1 km2, and is divided into three zones. It mainly distributes in the hill and slope where the elevation is higher than 250 m. There is little bauxite in the flat zone with low elevation. The distribution of bauxite in this area is verified preliminarily, which provides very effective instruction information for further exploration.
Key words: bauxite; alteration; independent component; information extraction; metallogenic prediction
