敦煌地块南缘多坝沟地区主要地质成矿特征及找矿方向

METALLOGENIC CHARACTERISTICS AND PROSPECTING DIRECTION OF DUOBAGOU AREA IN SOUTHERN MARGIN OF DUNHUANG BLOCK

多坝沟地区位于甘新边界敦煌地块南缘三危山金铁稀有金属宝石成矿带,成矿地质条件优越,但受自然条件的制约,工作程度偏低。本文以最新的研究资料和找矿成果为基础,结合区域成矿地质背景的综合研究,在区内划分了2个成矿亚带,其成矿作用具有多期次发育和多因素控制的特点。研究区主要成矿类型为岩浆热液型金矿、岩浆型铁铌钽钪矿、沉积变质型—接触交代型铁矿和沉积型铁矿等,主要成矿期有古元古代、早古生代、早二叠世、晚二叠世和新生代。结合区域找矿进展和成果,认为在八龙沟—崔木土成矿亚带具有寻找岩浆热液型金矿和花岗岩型铌钽矿找矿潜力,大红山—卡拉塔格成矿亚带具有寻找岩浆型铌钽钪矿、辉长岩型钒钛磁铁矿和沉积变质—接触交代复合型磁铁矿的前景。

Restricted by the natural conditions, the level of geological work has been low in Duobagou area, which has superior metallogenic geological condition and is located in the southern margin of the Dunhuang block. Based on the new research and prospecting breakthrough as the foundation, on the basis of regional geological background, the area is divided into 2 metallogenic belt, the metallogenic epoch and the development of multi factor control features. The main metallogenic types in the study area contain magmatic hydrothermal type gold ore, magmatic type niobium and tantalum ore, sedimentary metamorphic type-contact metasomatic iron ore and sedimentary type iron ore. The main metallogenic periods are Paleoproterozoic, early Paleozoic, Early Permian, Late Permian and Cenozoic. Combined with the regional prospecting achievements, there are prospecting potential that in Balonggou-Cuimutu metallogenic belt with magmatic hydrothermal type gold deposits and granite type niobium -tantalum ores, in Dahongshan -Kalatage metallogenic belt with magmatic type niobium -tantalum ores, scandium, gabbro type vanadium titanium magnetite ores and sedimentary metamorphic-contact metasomatism composite type magnetite.