安徽庐江泥河铁矿床赋矿闪长玢岩地球化学特征研究  

Geochemical characteristics of ore-bearing diorite porphyrite of the Nihe iron ore deposit in Lujiang,Anhui Province

作　　者：杨世学[1] 张靖怡[1] 张赞赞[1] 魏国辉[1] 

机构地区：[1]安徽省地质调查院,合肥230001

出　　处：《华东地质》2017年第4期241-249,共9页East China Geology

基　　金：中国地质调查局"安徽庐枞地区构造;岩浆演化与成矿作用的关系(编号:1212011120862)";"安徽庐枞地区隐伏及深部矿资源潜力调查(编号:12120114038001)";安徽省公益性地质调查项目"安徽省稀有;稀散元素矿产远景调查(编号:2016-g-2-16)";"安徽省庐枞地区与碱性岩有关的铀(钍)矿调查评价(编号:2016-g-1-7)"联合资助

摘　　要：玢岩型铁硫矿床是长江中下游地区重要的矿床类型,与隐伏闪长玢岩具有密切的成因联系,研究赋矿闪长玢岩的地球化学特征,对探讨玢岩型铁硫矿床的形成及演化、指导深部找矿具有重要意义。文章以庐枞盆地泥河玢岩型铁硫矿床赋矿闪长玢岩为研究对象,在对钻孔详细观察的基础上,研究赋矿闪长玢岩的岩石地球化学特征。该赋矿闪长玢岩具有中高硅含量,高钾富碱,低钛,高铝,富集Sr、K、Rb、Th、Ce等大离子亲石元素,亏损Nb、Ta、Ti、Zr、Hf等高场强元素,属于橄榄玄粗质系列岩石。结合Sr-Nd同位素特征,推测岩浆源区可能为富集型岩石圈地幔,分离结晶与同化混染共同影响岩浆的演化过程。Por p hy ry- l ike ty p e i ro n d e p o s i t s a r e o n e impor t a nt ty p e of p o lyme ta l l ic d e p o s i t s in th e Mid -dle-Lower Reaches of Yangtze River,and have genet ic relationship with concealed diori te porphyrite. The geochemistry study of ore-bearing diori te porphyrite is of signi ficance for invest igat ing deposi t genesi s and deep explorat ion. This study carried out l i thogeochemical analysi s of the ore-bearing diori te porphyrite in conjunct ion with detai led observation of dri l l ing cores. The ore-bearing diori te porphyrite of the Nihe iron deposi t is characterized by high Si〇2 , K a n d a l k a l i, low T i〇2 , r e la t iv e ly h ig h in L IL E s su c h a s S r, K ,Rb ,Th ,Ce,a n d d e ple te d in HSFEs su c h a s Nb ,T a ,T i,Z r,H f ,s u g g e s t in g th a t i t b e lo n g s ic rock. Based on the Sr-Nd isotopic features,it can be inferred that magmat ic source region should be en-riched mant le？ and evolut ion process of the magma was affected jointly by assimi lat ion and fractional crys-tallization.

关 键 词：赋矿闪长玢岩 地球化学特征 泥河铁矿床 庐江 安徽 

分 类 号：P611.1[天文地球—矿床学]