滇黔桂地区铝土矿地质特征及成矿规律研究OA

Bauxite is a critical strategic resource underpinning China's national economy and the development of emerging industries.The Yunnan-Guizhou-Guangxi(Dian-Qian-Gui)region,as China's second largest bauxite enrichment area,possesses complex metallogenic geological conditions.An in-depth study of its metallogenic patterns is of great significance for ensuring resource security.To reveal the metallogenic mechanisms of bauxite in this region and guide ore prospecting and prediction,this paper systematically reviews the regional geological background and selects typical bauxite-forming areas,including southeastern Yunnan-western Guangxi,central Yunnan,central Guizhou,and northern Guizhou-southern Chongqing.Through comparative analysis of deposit geological characteristics,ore-controlling factors,and genetic relationships,a regional metallogenic model is constructed.The research results indicate that bauxite deposits in the Yunnan-Guizhou-Guangxi region are primarily divided into two types:Paleozoic sedimentary type and Quaternary accumulation type,with diaspore being the dominant ore mineral in both.The Paleozoic sedimentary-type deposits not only represent an independent deposit type but also serve as the material foundation for the formation of Quaternary accumulation-type deposits.The two dominant metallogenic models in the region are the primary sedimentary model of"paleoweathering crust-transgressive(or lacustrine)sedimentation-diagenetic modification"in the Paleozoic,and the secondary enrichment model of"weathering and disintegration of primary deposits-accumulation in karst depressions"in the Quaternary.Notably,the unique accumulation-type bauxite deposits in southeastern Yunnan-western Guangxi are jointly controlled by the erosion of Paleozoic ore-bearing rock series and the development of modern karst landforms.The study concludes that bauxite mineralization in the Yunnan-Guizhou-Guangxi region exhibits distinct spatiotemporal inheritance,with paleogeographic environments and karst processes being key controlling factors.Future exploration efforts should focus on paleoweathering crust development zones and modern karst depression accumulation areas.This research provides a scientific basis for evaluating the resource potential and strategic planning of bauxite resources in southwestern China.