越南铝土矿地质特征及成因浅析  

Geological characteristics and genesis analysis of bauxite deposits in Vietnam

作　　者：韦启锋 农军年 韦守东 李庆华 WEI Qifeng;NONG Junnian;WEI Shoudong;LI Qinghua(China-ASEAN Geosciences Cooperation Center(Nanning),Nanning 430023,Guangxi,China)

机构地区：[1]中国-东盟地学合作中心(南宁),广西南宁530023

出　　处：《矿产与地质》2023年第3期501-506,共6页Mineral Resources and Geology

基　　金：广西自然资源厅“广西企业境外矿产资源战略性供应安全与保障调查评价”(桂自然办〔2022〕371号);广西科学技术厅“中—柬岩溶关键带科学与技术联合研究中心平台”(桂科AD20297091);广西科技厅“桂西与柬埔寨中酸性岩成岩成矿对比研究”(桂科AD22035195);广西地质矿产勘查开发局“东盟国家矿产与成矿规律综合集成和支撑服务”(桂地矿外〔2021〕3号)等项目共同资助。

摘　　要：越南地处环太平洋构造域和特提斯—喜马拉雅构造域的交汇部位,成矿条件优越,铝土矿资源丰富,但目前对越南铝土矿地质特征及成因的研究较少。文章在系统收集资料基础上,对越南铝土矿重要成矿区进行了实地踏勘考察,进而总结了越南铝土矿的地质特征、时空分布及矿床成因类型。越南铝土矿已探明储量约58亿吨,主要有岩溶型和红土型两种成因类型,并以红土型为主(已探明储量54亿吨)。越南北部主要发育岩溶型铝土矿,其成因与我国桂西地区类似,呈层状、透镜状集中分布于越南北部晚二叠世灰岩侵蚀面上,少量分布在泥盆纪灰岩风化面上,主要由富铝岩石经次生风化作用沉积形成;红土型铝土矿主要发育于中南部西侧高原地区,在印支地块新生代大型走滑伸展大背景下,地幔热物质沿深断裂上涌形成上新世—更新世大规模玄武岩,其后经风化作用形成红土型铝土矿。研究成果可为促进我国地勘单位和矿业企业“走出去”开展铝土矿资源勘查开发提供有价值的参考信息。Vietnam is located at the intersection of the Circum Pacific tectonic domain and Tethys-Himalaya tectonic domain,with super metallogenic condition and abundant bauxite resources.However,there are few researches on geological characteristics and genesis of bauxite deposits in Vietnam.On the basis of systematic data collection,this paper has carried out field investigation of important bauxite metallogenic areas in Vietnam,and has summarized the geological characteristics,spatial-temporal distribution and genetic types of bauxite deposits in Vietnam.There are proven reserves of 5.8 billion tons of bauxite in Vietnam,mainly including karst type bauxite and laterite type bauxite,and the latter is the main type(proven reserves of 5.4 billion tons).Karst type bauxite is mainly distributed in North Vietnam.Its genesis is similar to that of West Guangxi in China.The bauxite ore bodies,with layer and lenticular shape,are mainly distributed on the erosion surface of Late Permian limestone in North Vietnam,and a small amount is distributed on the weathering surface of Devonian limestone,which is formed by the deposition of aluminum rich rocks through secondary weathering.Lateritic bauxite is mainly developed in the plateau area in the west of Central-South Vietnam.Under the background of Cenozoic large-scale strike slip extension of the Indosinian Block,upwelling of the hot mantle material along the deep fault results in Pliocene-Pleistocene large-scale basalt,in which lateritic bauxite is subsequently formed through later weathering.The research result of this paper can provide the valuable reference information for promoting the geological exploration units and mining enterprises in China to"go out"to carry out the exploration and development of bauxite resources.

关 键 词：红土型铝土矿 岩溶型铝土矿 成因 资源勘查 越南 

分 类 号：P618.45[天文地球—矿床学]