矿物自动定量分析系统在含铝岩系岩矿分析中的应用——以陇东地区太原组为例  

Application of Mineral Automatic Quantitative Analysis System in the Petrology and Mineralogy Analysis of Aluminiferous Rock Series:Taking Taiyuan Formation in the Longdong area as an example

作　　者：马琛璐 井向辉[2,3] 贾连奇 李涵 王爱国[1] MA ChenLu;JING XiangHui;JIA LianQi;LI Han;WANG AiGuo(Department of Geology and State Key Laboratory of Continental Dynamics,Northwest University,Xi’an 710069,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,China;Research Institute of Exploration and Development,PetroChina Changqing Oil Field Company,Xi’an 710018,China)

机构地区：[1]西北大学地质学系和大陆动力学国家重点实验室,西安710069 [2]低渗透油气田勘探开发国家工程实验室,西安710018 [3]中国石油长庆油田分公司勘探开发研究院,西安710018

出　　处：《沉积学报》2025年第2期500-512,共13页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(41972143,41502148,42072127);长庆油田油气重大专项子课题(技2021-90-5)。

摘　　要：【目的】近年来,鄂尔多斯盆地陇东地区太原组含铝岩系的天然气勘探取得重大突破。然而,受传统光学显微镜的制约,含铝岩系的矿物学研究仍较为薄弱。【方法】本文使用全自动矿物分析系统TIMA(TESCAN Integrated Mineral Analyzer),结合薄片观察等手段,研究含铝岩系的矿物学特征,查明矿物组成及其赋存状态,详细测定矿物的种类、含量,并讨论其成因、总结矿物演化序列。【结果】该地区含铝岩系的主要矿物成分包括硬水铝石、菱铁矿、黄铁矿、伊利石、高岭石、鲕绿泥石等。伊利石主要是流体蚀变的产物,早期沉积高岭石为风化过程的产物,晚期成岩高岭石由后期硬水铝石硅化而成。锐钛矿和硬水铝石同期结晶,并形成于还原环境。早期的鲕绿泥石形成于喀斯特环境,并经过一段距离的运移到达成矿场所,晚期的鲕绿泥石形成与菱铁矿溶蚀有关。该地区含铝岩系中矿物形成于地表风化期、成矿期、后生期等三个阶段。【结论】对于含铝岩系这类矿物组成复杂、晶粒细小光学显微镜不易观察的样品,基于扫描电镜和能谱分析的TIMA能够快速、有效地识别含铝岩系的矿物组成,获取矿物含量和元素信息,并查明不同矿物之间共生、连生和包裹关系。[Objective]Recently,a breakthrough has been made in the gas exploration of the aluminiferous rock series from the Taiyuan Formation in Longdong area of Ordos Basin.However,the mineralogical studies of aluminous rock series are still relatively weak due to the constraints of conventional optical microscopy.This study aims to identify the mineral composition and its occurrence state,determine the elemental types and content of minerals in the ore in detail,discuss their mineral genesis,and summarize the mineral evolution sequence.[Methods]The aluminiferous rock series in this area was selected as the object of study.The mineralogical characteristics of the aluminiferous rock series were studied by using TIMA(TESCAN Integrated Mineral Analyzer),a fully automatic mineral analysis system of Czech Republic,combined with thin section observation and other means.[Results]The study shows that the main mineral components of the aluminiferous rock series in the Longdong area include diaspore,siderite,pyrite,illite,kaolinite,and oolitic chlorite.The main body of illite is the product of fluid alteration,the early sedimentary kaolinite is the product of weathering,and the late diagenetic kaolinite is formed by silicification of later diaspore.The simultaneous crystallization of anatase and diaspore was formed in a reducing environment.The early oolitic chlorite was formed in a certain karst environment and later migrated to the ore site after a certain distance.The late oolitic chlorite formation is related to the dissolution of siderite.The formation and evolution of minerals in bauxite rocks in this area can be summarized by:surface weathering,metallogenic,and epigenetic periods.[Conclusions]For samples of the aluminum rock series with complex mineral composition and small grains that are not easily observed by optical microscopy,TIMA based on scanning electron microscopy and energy spectrum analysis can quickly and effectively identify the mineral composition of the aluminiferous rock series,obtain mineral composition and

关 键 词：TIMA 含铝岩系 矿物成分 演化序列 陇东地区 

分 类 号：P618.71[天文地球—矿床学]