明矾石光谱在蚀变岩帽找矿勘查中的应用进展  

Advances of alunite spectrum in lithocap in the study of ore prospecting exploration

作　　者：白龙洋 代晶晶[1,2] 王楠 宋扬[1,2] 刘治博[1] BAI LongYang;DAI JingJing;WANG Nan;SONG Yang;LIU ZhiBo(State Key Laboratory of Deep Earth and Mineral Exploration,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100094,China;MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China)

机构地区：[1]中国地质科学院矿产资源研究所,深地探测与矿产勘查全国重点实验室,北京100094 [2]中国地质科学院矿产资源研究所,自然资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《岩石学报》2025年第5期1837-1850,共14页Acta Petrologica Sinica

基　　金：本文受国家自然科学基金地质联合基金(U2444212);中国地质科学院基本科研业务费专项经费(JKYZD202405);国家自然科学基金面上项目(42172332);中国地质调查项目(DD20230054、DD20230033);横向项目(2023KDG01001)联合资助详细信息。

摘　　要：蚀变岩帽是强酸性、高氧逸度的岩浆热液或混合地下水与围岩反应的产物, 属于浅成低温热液铜金矿床的重要找矿标志。明矾石作为蚀变岩帽中发育的最为常见的蚀变矿物之一, 对高硫化型浅成低温热液矿床的找矿勘查具有重要指示意义。近年来, 明矾石在找矿勘查应用中的应用效果已逐步突显, 特别是岩浆热液成因的明矾石通常可揭示深部斑岩矿化的存在。同时, 明矾石红外光谱及其地球化学特征已成为相关矿床勘查标识研究的重要方向, 其短波红外1480nm峰位、拉曼光谱161cm^(-1)峰位及161cm^(-1)、234cm^(-1)峰强、地球化学Na-K元素变化规律已被广泛应用于指示深部热液中心。然而, 明矾石的光谱学找矿勘查标识体系构建尚不够完善, 矿物光谱与地球化学特征之间的耦合机理性研究薄弱。本文系统阐述了不同成因环境下明矾石的矿物学特征, 探讨了明矾石光谱与其地球化学成分的影响因素, 提出了明矾石光谱及地球化学勘查标识构建过程中存在的问题, 并基于明矾石光谱勘查体系的不足指出了该矿物在地质勘查领域的未来发展方向。本文旨在为后续明矾石的勘查标识研究提供借鉴, 并为蚀变岩帽的找矿勘查提供理论与技术支撑。Lithocap is a product of reaction between strongly acidic and high oxygen fugacity hydrothermal or mixed with groundwater fluids and wall rocks, presenting as the key tracing criteria of epithermal Cu-Au deposit. Alunite hosted in the lithocap of high-sulfidation system is one of the representative alteration minerals, which is worth studying primarily in the aspect of prospecting exploration. The application effect of alunite in prospecting exploration has been gradually highlighted in recent years, especially the alunite formed in magmatic hydrothermal indicates location within porphyry mineralization. Meanwhile, the infrared spectrum and geochemistry of alunite have become the important directions in the research on exploration indicators. The variation corresponding to the peak position at short-wave infrared 1480nm and Raman 161cm-1 as well as geochemistry Na-K have been widely studied to reveal the deep hydrothermal center. However, the prospecting exploration model of alunite spectrum is insufficient, the coupling mechanism between mineral spectroscopy and geochemistry is weakly studied. This paper systematically described the mineralogical characterization of alunite from different environments, explored the influence factors of alunite spectrum and geochemical elemental variation, raised some questions in the establishment of alunite spectrum and geochemical indicators. The future research development in geological prospecting of alunite was induced based on the deficiency of alunite's spectrum prospecting system. This paper aims to provide a reference for the following prospecting indicator and offer theoretical support to the lithocap prospecting exploration in continental volcanic rocks.

关 键 词：蚀变岩帽 明矾石 光谱 矿物地球化学 找矿勘查 

分 类 号：P578.75[天文地球—矿物学] P614[天文地球—地质学] P624