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浦桑果铜多金属矿床是在南木林火山盆地内新近发现的矽卡岩型铜多金属矿床。文章对矿区内的花岗闪长岩、花岗闪长斑岩和闪长玢岩进行了岩石地球化学研究,结果表明:这些岩石的ω(SiO2)介于59.08%～67.28%,ω(Al2O3)为15.38%～16.86%,ω(MgO)为1.52%～4.06%,ω(TFeO)介于1.2%～3.46%,均属钙碱性系列。稀土元素总量为22.0×10-6～148.56×10-6,LaN/YbN比值为17.98～37.57,为轻稀土元素富集。花岗闪长岩、花岗闪长斑岩和闪长玢岩均相对富集Cs、Rb、Sr等大离子亲石元素(LILE),亏损高场强元素(HFSE)Th、U、Nb等,强负铕异常或弱负铕异常,无铈异常或弱铈异常。岩石学、岩石化学、微量元素研究表明,花岗闪长斑岩和闪长玢岩形成于中生代雅鲁藏布新特提斯洋向北部拉萨地体俯冲的岛弧环境,花岗闪长岩形成于青藏高原碰撞后伸展作用环境。
The Pusanguo copper polymetallic deposit is a skarn-type copper polymetallic deposit newly discovered in the South Mulin volcanic basin. The rock geochemical study of granodiorite, granodiorite porphyrite and diorite porphyry in the mining area shows that these rocks have a coercivity of 59.08% -67.28% ) Is 15.38% ~ 16.86%, ω (MgO) is 1.52% ~ 4.06% and ω (TFeO) is 1.2% ~ 3.46% The total rare earth elements ranged from 22.0 × 10-6 to 148.56 × 10-6, and the LaN / YbN ratio ranged from 17.98 to 37.57, indicating a light rare earth element enrichment. Granodiorite, granodiorite porphyrite and diorite porphyrite are relatively enriched in LILE, HFSE Th, U, Nb, etc., relatively rich in Cs, Rb and Sr , Strong negative europium anomaly or weakly negative europium anomaly, no cerium anomaly or weak cerium anomaly. Petrology, petrochemistry and trace element studies show that the granodiorite porphyry and diorite porphyrite are formed in the island arc environment of the Mesozoic Eocene Tethys Ocean to the subducted Lhasa terrane, the granodiorite Formed in the Tibetan Plateau stretching after the impact of the environment.