青藏高原及邻区层控型铅锌矿时空分布特征

摘要

The Paleozoic-Mesozoic multi-arc basin system and the tectonic framework of Cenozoic rapid uplift in the Tibetan plateau have resulted in specific temporal and spatial distribution of the Pb-Zn deposits and zoning of mineralization and led to the phenomenon that different tectonic units have different specific ore species. The stratabound Pb-Zn deposits in the study area are characterized by multi-epoch mineralization, with the Cambrian and the Devonian strata being the main ore-hosting horizons. Moreover, lots of lithofacies containing Pb-Zn deposits were formed during that period, and the carbonate platform facies was the advantageous ore-controlling facies, with dolomites as the main ore-bearing rocks. Large to superlarge Cenozoic lead-zinc ore bodies were also discovered in the study area, which were assigned to low-temperature thermal brine migration-filling type ore deposits. The authors hold that the uplift of the Tibetan Plateau in the Cenozoic might be an important factor responsible for the enrichment of this type of lead-zinc deposits. It is believed that so long as detailed studies are conducted, these Cenozoic ore deposits in the study area will show tremendous ore-prospecting potential.%青藏高原古生代—中生代复杂的多岛弧盆系演化和新生代高原急剧隆升的构造格局造就了层控型铅锌矿特定的时空分布和成矿作用的分带性.在不同类型的构造单元内具有特征的成矿专属性和矿床类型.青藏高原及周缘层控型铅锌矿有多时代成矿的特点,寒武系和泥盆系是主要赋矿层位.古生代—中生代铅锌矿合矿层岩相古地理具有多样性,以台地相作为控矿优势相,尤其以白云岩作为容矿岩石的矿床居多.另外新生代地层作为主要容矿层之一,发育有大型甚至特大型的层控铅锌矿体,为低温热卤水运移充填矿床.推测青藏高原在新生代快速隆升是该类矿床富集成矿的重要控矿因素.随着研究的深入和勘查的进展,这种新生代矿床将在该区显示出巨大的找矿潜力.