地质学报2018，Vol.92Issue(1)：77-93,17.
赣北昆山钨钼铜矿床花岗岩地球化学及Hf同位素研究
Geochemical and Hf Isotopes of Granites in the Kunshan W-Mo-Cu Deposit, Northern Jiangxi Province
摘要
Abstract
The Kunshan W-Mo-Cu deposit in Northern Jiangxi which is located in the central area of Jiuling tungsten-polymetallic ore concentration region,is a medium-large scale tungsten-polymetallic deposit discovered in Dahutang area recently.Ore bodies in the form of quartz vein occur in the external contact zone between the Yanshanian porphyritic granite (～ 152Ma) and the low grade metamorphic rock of Neoproterozoic Shuangqiaoshan Group.In addition to porphyritic granite,there are granite porphyry veins (～ 136Ma) outcropped in the Kunshan deposit.In this peper,detailed studies on the petrology,geochemistry of Yanshanian intrusions and analysis of zircon Hf isotopes of porphyritic granite which is closely related to mineralization in the deposit are conducted.Both porphyritic granite and granite porphyry are characterized as high silicon (SiO2 =71.35％～76.55％,73.12 ％～75.15％),high potassium (K2O=3.81％～5.25％,5.14％～6.26％),calc-alkaline series of peraluminous granite (A/CNK=1.07～1.26,1.06～1.43,and the average is more than 1.1);enrichment in LREEs,strong LREE/HREE fractionation and significant negative Eu anomalies (δEu=0.34～0.58、0.20～0.32);low zircon saturation temperatures (711～ 761℃ and 727 ～ 766℃ respectively),which suggest that they are both high fractional S-type granites.The εHf(t) values of porphyritic granite vary from-8.80 to 4.48 with the two-stage model ages tDM2 of 917Ma to 1757Ma.It is indicated that the source region of the granite were mostly from the Neoproterozoic Shuangqiaoshan Group,and the Yanshanian magmatic activity is related to the tectonic conversion of The Lower Yangtze region in Late Jurassic.Based on the petrologic,geochronological,geochemical and Nd-Hf isotopes characters of granites in Dahutang area,it is concluded that the Kunshan deposit has a similar magmatic evolution sequence with the Dahutang deposit which originated from the same deep magma chamber,and then intruded discontinuously after differentiation process.关键词
花岗岩/地球化学/锆石Hf同位素/石英脉型钨矿/昆山矿区/大湖塘Key words
granites/geochemistry/zircon Hf isotope/Kunshan deposit/Dahutang area引用本文复制引用
张明玉,丰成友,李大新,王辉,周建厚,叶少贞,汪国华..赣北昆山钨钼铜矿床花岗岩地球化学及Hf同位素研究[J].地质学报,2018,92(1):77-93,17.基金项目
本文由国家重点研发计划课题(编号:2016YFC0600205)、国家重点基础研究发展计划973课题(编号:2012CB416704)、中国地质调查局高层次地质人才培养计划(201309)和青年地质英才计划(201112)联合资助. （编号:2016YFC0600205）
