浙江省衢州地区新路火山岩盆地西段铀成矿模式  

Uranium metallogenic model for west segment of Xinlu volcanic basin in Quzhou area, Zhejiang Province

作　　者：韩效忠[1,2] 刘蓉蓉[1] 刘权[1] 王明太[1] 腰善丛[1] 惠小朝[2] 

机构地区：[1]核工业北京地质研究院,北京100029 [2]中国地质大学,北京100083

出　　处：《矿床地质》2010年第2期332-342,共11页Mineral Deposits

基　　金：工业与信息部国防科学局核能开发三期资助成果

摘　　要：文章在对研究区内白鹤岩、大桥坞和杨梅湾重点矿床成矿特征、控矿规律详细分析的基础上,指出该区铀成矿主要受构造、热液蚀变和侵入岩体的联合控制。依据主要控矿因素,建立了该区3阶段铀成矿模式:①火山喷发和岩浆侵入阶段;②大规模铀成矿阶段;③后期剥蚀矿体改造阶段。指出火山期后的岩浆侵位为铀成矿准备了含矿热液流体,NE、NNE向深大断裂为主要导矿构造,NW向次级断裂为主要的储矿构造,岩浆侵位和不同规模的断裂体系构成了含矿热液形成、运移和富集的完整过程。本区铀成矿在时间上可划分为2个阶段,早期为125～115Ma,晚期为90.9～70.2Ma,两期铀成矿与两期岩浆侵位相对应;在空间上呈"三层楼式"分布:即浅部为与砾岩层和隐爆有关的"白鹤岩式"铀矿化,中部为与赤铁矿化、萤石化、金属硫化物化有关的"大桥坞式"铀矿化,深部为与钠交代、硅化有关的"杨梅湾式"铀矿化。在此基础上,提出矿区外围找矿重点区域为:距NE、NNE向深大断裂出露线2km范围内上盘,且NWW向次级断层和水云母化蚀变强烈发育的地区;已知矿区深部找矿层位为:大桥坞矿床深部的"杨梅湾式"铀矿化、白鹤岩矿床深部的"大桥坞式"和"杨梅湾式"铀矿化。Based on a detailed analysis of metallogenic characteristics and regularity of three important deposits, i.e., Baiheyan, Daqiaowu and Yangmeiwan, this paper holds that the uranium metallogeny is controlled jointly by structure, hydrothermal alteration and intrusive rock in the study area. A three stage model for uranium metallogeny has been constructed according to the following main ore-controlling factors： ① the first stage-volcanic eruption and magma intrusion, ② the second stage-uranium metallogeny, and ③ the third stage-denudation and ore body reformation. It is pointed out that the magmatic intrusion supplied metallogenic hydrothermal fluids, the NE and NNE-striking deep faults constituted the principal channels for hydrothermal fluids whereas the NW-trending secondary faults provided room for uranium precipitation. All of these factors constituted an integrated metallogenic system comprising the formation, movement and enrichment of ore-bearing hydrothermal fluids. There existed two uranium metallogenic stages corresponding to the magmatic intrusion, i.e., 125～115 Ma and 90.9～70.2 Ma. The ‘three-layer’ uranium metallogenic model in space is put forward in this paper： the upper part is the Baiheyan stratified ore body associated with conglomerate, the middle part is the Daqiaowu veinlike ore body related to hematite, fluorite and sulfide, and the lower part is the Yangmeiwan ore body having to do with alkali-metasomatism and silicification. On such a basis, the favorable ore-prospecting places in the periphery of the ore district are delineated, which are located on the hanging wall about 2 km from the exposed lines of the NE and NNE-striking deep faults, with well-developed NWW-striking secondary faults and intense hydromicazation. The deep prospecting horizons for uranium metallogeny in the ore district are ‘Yangmeiwan’ uranium mineralization below the Daqiaowu ore deposit and the ‘Daqiaowu’, ‘Yangmeiwan’ style uranium mineralizations below the Baiheyan ore deposit.

关 键 词：地质学 火山岩 铀成矿模式 浙江省衢州 

分 类 号：P619.14[天文地球—矿床学]