【摘要】：斯弄多銀(金)-鉛-鋅礦床是岡底斯南緣林子宗群火山巖中發(fā)現(xiàn)的首例低硫化淺成低溫?zé)嵋盒偷V床,其發(fā)現(xiàn)對于完善區(qū)域成礦系列,開拓區(qū)域找礦方向都具有重要的意義。本文采用遙感技術(shù)與短波紅外技術(shù)相結(jié)合的方法,通過三維建模重現(xiàn)了地表-地下的蝕變礦物組合,形成了星-空-地一體化的三維蝕變填圖。本文采用多光譜遙感ASTER數(shù)據(jù)提取了地表圍巖蝕變信息,通過遙感波段比值算法的鐵染指數(shù)(b2+b3)/b1、鎂羥基指數(shù)(b6+b9)/(b7+b8)、鋁羥基指數(shù)(b5/b8)+(b6/b9)分別圈定了礦區(qū)地表含有Fe~(3+)、Fe~(2+),Al-OH和Mg-OH等基團(tuán)的蝕變礦物信息;采用短波紅外技術(shù)提取了巖心中的絹云母、蒙脫石和伊利石等礦物,并確定了地下的蝕變礦物組合。研究表明,(1)地表蝕變中的Al-OH蝕變信息與鉆孔中絹云母的分布非常吻合,遙感的Al-OH信息可作為重要的找礦線索;(2)根據(jù)地下蝕變礦物的種類分布,能夠確定地表鐵染蝕變礦物主要表現(xiàn)為大量褐鐵礦化(野外特征明顯)、少量黃鉀鐵礬及絹云母;(3)絹云母形成環(huán)境的不同導(dǎo)致其二八面體結(jié)構(gòu)發(fā)生變化:Al~ⅥAl~Ⅳ?Mg~ⅥSi~Ⅳ和Fe?Mg,是Mg-OH基團(tuán)與Al-OH信息在地表部分疊合的重要原因;(4)鉆孔中伊利石反射光譜特征參數(shù)計算表明,伊利石結(jié)晶度(SWIR-IC)在鉆孔中呈規(guī)律性變化,近礦部位SWIR-IC(1.1~1.4)值域較低,說明伊利石形成溫度較低,可能是黏土礦物成巖過程中蒙脫石向伊利石的轉(zhuǎn)化遞進(jìn)反應(yīng),遠(yuǎn)礦段SWIR-IC(1.6~2.1)值域較高,說明該礦物較近礦段而言形成溫度相對較高,是絹云母伊利石化的具體反映。
[Abstract]:The silver (gold) -lead-zinc ore deposit in Sinondo is the first low-sulfide epithermal hydrothermal deposit found in the volcanic rocks of Linzizong group in the southern margin of Gangdes. The discovery of the deposit is of great significance to the improvement of regional metallogenic series and the exploration direction of regional prospecting. In this paper, by using the method of remote sensing and short-wave infrared technology, the alteration mineral assemblage between surface and underground is reconstructed by three-dimensional modeling, and a three-dimensional alteration mapping is formed. In this paper, multispectral remote sensing ASTER data are used to extract the alteration information of surrounding rock. The iron-dye index (b2b3) / b1, magnesium hydroxyl index (b6b9) / (b7b8) and aluminum hydroxyl index (b5/b8) (b6/b9) obtained by the remote sensing band ratio algorithm have been used to delineate the alteration mineral information of Fe~ (3) Fe2 + Al-OH and Mg-OH groups in the surface of the mining area, respectively. The sericite, montmorillonite and Illite minerals in the core were extracted by short-wave infrared technique, and the altered mineral assemblage was determined. The results show that (1) the distribution of Al-OH alteration information in surface alteration is in good agreement with the distribution of sericite in boreholes, and the Al-OH information of remote sensing can be used as an important prospecting clue; (2) according to the species distribution of underground altered minerals, It can be determined that the surface iron-stained altered minerals are mainly characterized by a large amount of limonite (with obvious field characteristics), a small amount of vitriol and sericite, (3) the dioctahedron structure changes due to the different forming environments of sericite, and the structure of dioctahedron changes as a result of the variation of the structure of dioctahedron. Mg~ 鈪，

本文編號：2259870