华南钨和锡大规模成矿作用的差异及其原因初探_华仁民

2010年2月Feb.,2010矿床地质

M IN ERAL D EPOSI T S

第29卷第1期

Vol.29No.1

文章编号:0258-7106(2010)01-0009-15

华南钨和锡大规模成矿作用的差异及其原因初探X

华仁民,李光来,张文兰,胡东泉,陈培荣,陈卫锋,王旭东

(内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,江苏南京210093)

摘要钨和锡都是中国的优势矿产资源,主要分布在华南尤其是南岭及其邻近地区,关系密切、相互共生,但两者之间仍然存在着很明显的差异。在空间分布上表现为东钨西锡:南岭东段,钨矿密集产出;中段,钨锡并重,但锡矿化明显增强;西段则为大规模锡成矿作用。在成矿时代上,钨和锡都以160~150M a为成矿高峰期,但锡还有雪峰期、印支期成矿作用,以及燕山晚期的又一个成矿高峰期。锡的成矿作用及与其相关的花岗岩类显示出与地幔物质有较为密切的关系,因此,锡的大规模成矿作用或发生在有地幔物质参与的/十-杭带0附近,或发生在地壳强烈拉张的燕山晚期。钨与锡在元素地球化学性质上的差异,以及华南东、西两部分在构造背景、沉积物特征和岩浆活动等方面的差异,是造成华南钨与锡大规模成矿作用差异的根本原因。

关键词地质学;钨;锡;大规模成矿作用;差异;华南

中图分类号:P618.67;P618.44文献标志码:A

A tentative discussion on differences between large-scale tungsten

and tin mineralizations in South China

H UA RenMin,LI GuangLai,ZHANG WenLan,H U DongQuan,

CH EN PeiRong,CH EN WeiFeng and WANG XuDong

(State K ey Labor ator y for M iner al Deposit Research,School of Earth Science and T echnolog y,

N anjing U niversity,Nanjing210093,Jiangsu,China)

Abstract

Both tungsten and tin ar e the most prevailing mineral resources in rg e-scale tung sten and tin mineralizations too k place mostly in South China,especially in the N anling M ountains and the neighboring areas.T he two elements ar e v er y closely r elated to and accompanied wit h each other and always occur together in most or e deposits.Ho wever,differences do ex ist between tungsten and t in miner alizations in many aspects.Spat ial distribution shows that the eastern sector of the N anling M ountains is character ized by strong and dense W mineralizat ion,w hile Sn mineralization becomes stronger westwards.China's tw o lar gest Sn or e deposits are dis-tr ibuted in the western margin of the South China fold system.Although both tungsten and tin mineralizations have the same highest or e-forming epoch of160~150M a,the t in miner alization is spanned fr om t he late Xuefeng Period(~800M a)to L ate Yanshanian M ov ement(80M a).T he L ate Yanshanian Mov ement is in fact another highlight of tin mineralization.T he tin-bearing g ranite and t in miner alization show much closer relationship with the participatio n of mantle derived mat erials than tungsten mineralizatio n. T herefore,the larg e-scale tin mineralization took place either near the so-called Sh-i Hang Zone where long-term deep faulting w as ac-tiv ated and A-ty pe granites w er e emplaced or during t he L ate Yanshanian per iod when the South China continent was in a strong ten-sional geodynamic environment.T he pr incipal factors responsible for these differ ences may include the div ersity of geochemical proper-ties betw een the two elements and the differences in tectonic backgr ounds,str atigraphic char acteristics and magmatic activities be-tw een the eastern part and the western par t of Sout h China.

X本文得到国家重点基础研究发展计划(2007CB411404)及国家自然科学基金重点项目(40730423)的资助

第一作者简介华仁民,男,1946年生,教授,主要从事矿床学研究与教学。Email:huarenmin@

收稿日期2009-10-12;改回日期2009-12-01。许德焕编辑。