西藏林周县普琼朗铁矿地质特征及找矿方向

GEOLOGICAL CHARACTERISTICS AND PROSPECTING TARGET OF THE PUQIONGLANG IRON DEPOSIT, TIBET

以在勒青拉及其邻区开展矿产资源大调查项目成果为基础,对林周县普琼朗铁矿的成矿地质背景、矿床地质特征、地球物理特征、矿床成因、找矿前景等,进行了比较详细地研究。结果表明,喜马拉雅早期为西藏冈底斯岛弧造山带重要的富铁矿成矿期,普琼朗铁矿是产于喜马拉雅早期居布札日花岗闪长岩围岩接触带中的,岩桨期后中低温热液矽卡岩型交代一充填矿床。该矿是产于花岗闪长岩围岩接触带的矽卡岩和矽卡岩化灰岩中的大型矿床,在矿区外围找矿潜力巨大。矿体呈脉状、透镜状、似层状。矿体产出部位严格受矿区二叠系洛巴堆组,蒙拉组碳酸盐岩层位及其层间破碎带,以及近东西向断层破碎带的控制。容矿岩石主要为二叠系洛巴堆组,蒙拉组矽卡岩、矽卡岩化灰岩。矿石矿物主要为磁铁矿,次为黄铜矿、蓝铜矿;脉石矿物主要为方解石、石英、透辉石、石榴子石等。在综合研究基础上,提出了主要找矿标志和找矿方向,为区内找矿突破提供了新思路和新资料。同时该矿的发现,为冈底斯岛弧造山带富铁矿找矿突破奠定了基础。

On the basis of the mineral resource survey of the Puqionglang in LinZhou of Tibet, this paper deals with the geological settings, geological characteristics, geophysical characteristics, ore genesis and prospecting perspective of Puqionglang iron deposit. The study results show that the early Himalayan Period was an important metallogenic epoch for rich iron deposits in the Gangdise arc orogen of tibet. The Puqionglang iron deposit is located in the skarn and skarnization limestone in contacting belt of the Jubuzhari granite body in the early Himalayan Period, and is a postmagmatic meso. The ore bodies are mainly in veins, lenses and layered in marble. The ore bodies is strictly controlled by carbonate rock of the Permian Luobadui and mengla formation and the E-W orientation fracture zones in stratum layer. The host rocks are mainly skarn and skarnization limestone of the permian luobadui and mengla formation. Ore minerals are mainly magnetite, chalcopyrite and azurite etc.. Vein minerals are mainly in quartz, Calcite, diopside and garnet etc.. The potential resource quantity of Puqionglang iron deposit is huge and proposed prospect searching for the same type iron deposit in the outside, too. Based on the geological features, ore-controlling factors, prospecting criteria and target for iron deposit in this region are discussed. The discovery of Puqionglang iron deposit initiate a new idea and a important foundation for prospecting for the type of iron deposit in the Gangdise Arc orogen of tibet.