中南大学学报（自然科学版）2017，Vol.48Issue(1)：212-222,11.DOI:10.11817/j.issn.1672-7207.2017.01.029
湖南锡田和邓阜仙燕山期花岗岩的源区差异及其意义
Difference of sources of the Yanshanian Xitian and Dengfuxian granites in Hunan Province and their implication
摘要
Abstract
In order to explore the effect of different source regions on W and Sn polymetallic mineralization,comparative studies of petrography and geochemistry of element on zircon and rock were conducted on two-mica granites in Yanshanian complex mass from Xitian and Dengfuxian in Hunan Province.The results show that Xitian and Dengfuxian'two-mica granites are rich in silicon,aluminum and alkali.Relative high values of 10 000w(Ga)/w(Al) (3.58-4.20 and 2.04-4.11,respectively) indicate that both granites are A-type granites,w(Nd)/w(Th) ＜ 15 and w(Th)/w(U) ＞ 1 suggest that both granites originate from crust.However,Xitian granite has lower phosphorus,higher rare earth elements,more negative Eu anomaly,and lower degree of fractionation between light and heavy rare earth elements than that of Dengfuxian granite.The REE distribution pattern of Xitian granite is symmetrical type while that of Dengfuxian granite is right type.Moreover,magma crystallized temperatures in Xitian and Dengfuxian calculated by using components of zircon are 823-945 ℃ and 613-922 ℃,respectively,and lg(fo2/105 Pa) are-14.7 and-16.8,respectively,which shows that Xitian and Dengfuxian granites are A-type granites formed in an extensional tectonic setting.They are also products of the partial melting of proterozoic crust,and their source regions mainly contain clastic rock.But there are more igneous rocks in the source region of Xitian granite.As a result,two crust-original granites with spatially adjacency and the same period can still come from different sources and diagenetic environments,which has impact on mineralization.关键词
燕山期花岗岩/源区/环境/锡田/邓阜仙Key words
Yanshanian granite/source region/environmental/Xitian/Dengfuxian分类
天文与地球科学引用本文复制引用
邓渲桐,曹荆亚,吴堑虹,孔华,奚小双..湖南锡田和邓阜仙燕山期花岗岩的源区差异及其意义[J].中南大学学报（自然科学版）,2017,48(1):212-222,11.基金项目
中国地质调查局整装勘查项目(12120114052101)(Project(12120114052101) supported by Integrated Exploration Program of the China Geological Survey) （12120114052101）
