中文摘要：

为揭示额仁陶勒盖银矿床火山岩与成矿作用的关系,对矿区内赋矿围岩火山岩展开了系统的年代学和元素地球化学研究。成果揭示：（1）赋矿围岩粗面安山岩的单颗粒锆石U-Pb年龄为（173.4±4.6）Ma;（2）粗面安山岩具有富集大离子亲石元素、亏损高场强元素以及弱的负铕异常的特征;对比洋壳成分,成矿元素呈现强烈亏损V、Cr、Ni、Co、Mo、Cu,富集W、Bi、Pb和相对富集Au、As、Sb、Te以及相似的Zn、Ag、B含量为特征。结合前人的研究成果,认为矿区内火山岩是成矿早期的产物,岩浆起源于流体交代过的大洋性质的岩石圈地幔,岩浆演化过程中有少量斜长石等矿物分离结晶作用和微弱的地壳物质混染,形成的构造环境可能为华北板块、蒙古块体与西伯利亚板块对接碰撞后的初期地壳伸展环境,且该阶段火山作用不具有直接提供成矿流体的属性,提供成矿流体的岩浆作用可能是早白垩世早期石英二长斑岩岩浆（138 Ma）。

英文摘要：

In order to reveal the relationship between volcanic rocks and mineralization in the Erentaolegai silver deposit,the ore-hosting volcanic rocks were selected for systematic studies of zircon U-Pb geochronology and whole-rock geochemical analysis. The results show that（ 1） the ore-hosting trachyandesites yielded a zircon U-Pb age of（ 173. 4 ± 4. 6） Ma,（ 2） the trachyandesites are characterized by the enrichment of large ion lithophile elements and depletion of high field strength elements with slightly negative Eu anomalies. Compared with the oceanic crust components,the ore-forming elements are characterized by strong depletion of V,Cr,Ni,Co,Mo and Cu elements,but enrichment in W,Bi and Pb elements,relative enrichment in Au,As,Sb and Te elements,withsimilar contents of Zn,Ag and B elements. In combination with previous studies,it is suggested that the volcanic rocks were formed at the early stage of mineralization. The magma of trachyandesites could be originated from the lithosophere mantle which had suffered fluid metasomatism. During the magma evolution,magma underwent slightly fractional crystallization（ e. g. plagioclase） and continental crust contamination. The volcanic rocks were formed at the early stage of extensional environment after the convergence or collision among the North China plate,the Mongolian plate and the Siberia plate. Moreover,the volcanism at this episode did not provide the ore-forming fluid directly,the magmatism that provided the ore-forming fluid should be the quartz-monzonite porphyry magma in the Early Cretaceous（138 Ma）.