摘要
根据一些热液矿床和赋矿岩浆岩的同位素年龄资料,结合矿床地质研究表明,其成岩成矿时差序列为钨铍铌钽→铜铅锌→金银→萤石依次增大。该序列与成矿元素的S_(298)~0/di值递增序列一致,也与矿床的成矿温度从高到低、深度由深至浅、成矿流体来源以岩浆热液到大气降水为主的成矿特征一致。并且随着成岩成矿时差增大,含矿构造由较密集分布的节理或裂隙转变为非常稀疏分布的断裂或断层。
Based on isotopic ages of some hydrothermal deposits and host magmatic rocks in ombination with geological characteristics of these deposits, the authors have reached the ollowing conclusions:1. Time intervals between the formation of host rock and the ineralization for fluorite, gold-silver, lead-zinc(copper)and tungsten-beryllium iobiumtantalum deposits are in order of tungsten-beryllium-niobium-tantalum (≈0×10~6a)copper-lead-zinc (10×10~6～3×10~6a)<gold-silver (30×10~6～60×10~6 a) <fluorite(40×10~6～010~6 a).Such time interval sequence is in agreement with the sequence of ore-forming sequence rranged in increasing s_(298)~0/di values (W, B, Mo, Sn, Nb, Ta<Zn, Cu<Ag, Au,Pb<Ca, ),suggesting that the relative mobility of ore-forming elements which is related to their hysical-chemical properties must be the major factor causing the formation of host rock and he ineralization of these deposits.2. The above time interval sequence coincides with the ore-orming evolutionary trend that temperature gradually falls, depth becomes smaller, and(to be ontinued on p.105) (continued from p.112)ore-forming fluids vary from magmatic solution to eteoric water as the dominant source, indicating that the time intervals between the formation f host rock and the mineralization could to a certain extent reflect genetic characteristics f re deposits.3. With the growing time interval, the ore-bearing structure commonly changes from rowded joints of fissures(as seen in tungstenl-beryllium deposits) to sparsely-distributed aults or fracture zones (as observed in fluorite and gold-silver-lead-zinc deposits). This uggests that, through the study of oreforming time or time interval between the formation of ost rock and the mineralization,the physical-chemical properties of ore-forming elements might e conncected with features of ore-bearing structure, and this seems to be of great ignificance o the study of structural geochemistry.
出处
《矿床地质》
CAS
CSCD
北大核心
1992年第2期106-112,共7页
Mineral Deposits
基金
浙江省自然科学基金的部分内容
