摘要
甘肃龙首山铀成矿带是中国内陆一条重要的铀成矿带。芨岭铀矿床是龙首山成矿带中典型的碱交代型铀矿床,蚀变种类繁多,且与铀矿化关系密切,利用航空高光谱技术可以从宏观上获取芨岭铀矿床地表蚀变、构造、岩性分布信息,为芨岭矿床及周边铀多金属矿产勘查提供依据。本文采用CASI/SASI/TASI航空高光谱遥感技术,对甘肃龙首山地区芨岭碱交代型铀矿区及周围地表出露的热液蚀变进行了研究,识别出了碱性长石、赤铁矿、透闪石、中铝绢云母、高岭石、石英(硅化)等与碱交代热液作用演化密切相关的蚀变矿物,并将蚀变矿物与构造、岩性等要素进行了综合分析。研究表明,碱性长石、透闪石、中铝绢云母和石英(硅化)等蚀变矿物分别代表了芨岭及周围地区碱交代热液作用过程中早期碱交代、中期中性交代、晚期酸性交代等不同演化阶段的热液蚀变作用;芨岭铀矿区碱交代热液作用的主要通道是区域不整合面、深大断裂、不同岩性接触带的复合体,马路沟铀矿控矿断裂的芨岭矿区段明显发育透闪石、中铝绢云母、硅化与碱交代作用相关的热液蚀变。根据芨岭铀矿床的航空高光谱遥感特征,提出了龙首山碱交代型铀矿找矿的主要预测判据。这些判据对龙首山的铀矿找矿新区预测和老矿点、异常点的新评价具有重要的意义。
The Longshoushan uranium metallogenic belt in Gansu Province is an important uranium metallogenic belt in China. Jiling uranium deposit is a representative alkali-metasomatism type uranium deposit in Longshoushan metallogenic belt. There are a wide variety of alterations in Jiling deposit. And these alterations have close relation to the uranium mineralization. The airborne hyperspectral technique can be used to obtain the surface alteration, structure and lithology distribution information of Jiling uranium deposit from a macroscopic perspective, which provides a basis for the uranium and polymetallic mineral exploration in Jiling deposit and its adjacent area. In this article, CASI/SASI/TASI airborne hyperspectral remote sensing techniques have been applied to the identification of hydrothermal alterations in Jiling alkali-metasomatism type uranium deposit as well as its adjacent district in Longshoushan area, Gansu Province. A variety of alteration minerals have been identified including alkali-feldspar, hematite, tremolite, medium-Al sericite, kaolinite, quartz and so on. These minerals are closely related to the alkali-metasomatism hydrothermal action in Jiling deposit. Besides,comprehensive analysis on alteration mineral, structure and lithology information in Jiling uranium deposit has been made. Study shows that the alteration minerals such as alkali-feldspar, tremolite, medium-Al sericite and quartz separately represent the different stages of hydrothermal alteration process in Jiling uranium deposit and its adjacent area, namely the early alkali-metasomatism stage, the middle neutral-metasomatism stage and the late acid-metasomatism stage. The main channel for alkali-metasomatism hydrothermal action is the composite of regional unconformity surface, deep and large faults, and contact zones of different lithologic units. The uranium mineralization zone in Jiling deposit is controlled by Malugou fault. In the uranium mineralization zone,tremolite, medium-Al sericite, and silicification are evident. And these alteration minerals have close relation to alkali-metasomatism in Jiling deposit. According to the airborne hyperspectral remote sensing charateristics in Jiling deposit, the main prediction criteria for the prospecting of alkali-metasomastism type uranium deposits in the Longshoushan Mountain are proposed. These criteria are of great significance for the prediction of new favorable uranium exploration areas and the new evaluation of old uranium mineralization stations and anomalies in the Longshoushan area.
作者
叶发旺
孟树
张川
邱骏挺
王建刚
刘洪成
武鼎
YE Fawang;MENG Shu;ZHANG Chuan;QIU Junting;WANG Jiangang;LIU Hongcheng;WU Ding(Beijing Reseach Institute of Uranium Geology,Beijing 100029,China;National Key Lab of Remote Sensing Information and Image Analysis Technology,Beijing 100029,China)
出处
《地球信息科学学报》
CSCD
北大核心
2019年第2期279-292,共14页
Journal of Geo-information Science
基金
中核集团龙腾二期项目(遥LTY1604)
国家自然科学基金项目(41772354)~~
关键词
CASI/SASI/TASI航空高光谱遥感
矿物识别
热液活动通道
碱交代型铀矿
甘肃龙首山地区
CASI/SASI/TASI airborne hyperspectral remote sensing
minerals identification
channels for hydrothermal activity
alkali-metasomatism type uranium deposit
Longshoushan area in Gansu province