| 张广宁.滇西马厂箐复式岩体岩浆混合作用：岩石学与地球化学证据[J].地质与勘探,2015,51(4):599-609 |
| 滇西马厂箐复式岩体岩浆混合作用：岩石学与地球化学证据 |
| Magma mixing in the Machangjing copper-bearing alkali-rich porphyry of western Yunnan: evidence of petrology and geochemistry |
| 投稿时间：2015-04-03 修订日期：2015-06-18 |
| DOI： |
| 中文关键词: MME暗色包体 富碱花岗斑岩 岩浆混合作用 马厂箐 滇西 |
| 英文关键词: mafic enclaves, magma mixing, mixing mechanism, machangjing copper deposit, western Yunnan |
| 基金项目:国家973计划（2015CB452600）中国西南特提斯典型复合成矿系统及其深部驱动机制、北京市优秀博士学位论文指导老师科研项目（20111141501）和国家973计划（2009CB421000）三江特提斯复合造山与成矿作用联合资助 |
|
| 摘要点击次数: 2583 |
| 全文下载次数: 5511 |
| 中文摘要: |
| 滇西马厂箐铜矿区含矿斑岩体中的暗色包体与其寄主富碱花岗斑岩具有相似的地球化学的特征。寄主花岗斑岩SiO2含量为65.10%~70.60%，Al2O3为14.65%~17.55%，MgO为0.80%~1.70%，CaO为0.43%~1.92%，Na2O+K2O为8.25%~12.23%。受混染包体SiO2为62.50%~77.30%，Al2O3为10.00%~15.70%，MgO为0.75%~3.82%，CaO为0.86%~2.15%，Na2O+K2O为7.68%~10.22%。二者稀土配分曲线都是典型的右倾型配分模式，轻重稀土分馏明显，富集轻稀土亏损重稀土。寄主岩具有高Sr（392.00×10-6~919.00×10-6）、低Y（10.10×10-6~17.10×10-6）、低Yb（1.00×10-6~1.40×10-6），高Sr/Y（33.24×10-6~104.43×10-6）、高（La/Yb）N（36.08×10-6~89.09×10-6）特点，暗色包体也具有高Sr（314.00×10-6~652.00×10-6），低Y（7.20×10-6~15.10×10-6）、低Yb（0.60×10-6~1.50×10-6）特征。通过对混染MME地球化学特征分析，结合前人对未混染或弱混染包体的研究资料，提出马厂箐复式岩体和其中的MME可能与该地区地幔玄武岩的底侵作用有关, 而这种玄武岩底侵导致的不同岩浆混合作用可能是马厂箐铜矿的部分成矿条件。 |
| 英文摘要: |
| The mafic microgranular enclave (MME) and its host granite porphyry in the Machangjing mine have similar chemical characteristics and similar age. The host granite is rich in SiO2(65.10%～70.60%), Al2O3(14.65%～17.55%) with total alkalis (Na2O+K2O)(8.25%～12.23%), but poor in MgO(0.80%～1.70%) and CaO(0.43%～1.92%). The MME has high content of SiO2 (62.50%～77.30%), Al2O3(10.00%～15.70%) with total alkalis (Na2O+K2O)(7.68%～10.22%), but low content of MgO(0.75%～3.82%) and CaO(0.86%～2.15%). The host porphyry contains much Sr (392.00×10-6～919.00×10-6), Sr/Y(33.24×10-6～104.43×10-6) and (La/Yb)N(33.24×10-6～104.43×10-6), while little Y(10.10×10-6～17.10×10-6) and Yb(1.00×10-6～1.40×10-6). Meanwhile the MME is also high in Sr(314.00×10-6～652.00×10-6), but low in Y(7.20×10-6～15.10×10-6) and Yb(0.60×10-6～1.50×10-6). Rare earth elements distribution curves of both MME and host porphyry are typical of the right type patterns, and their light and heavy rare earth element fractionation is obvious. Both are rich in light rare earth elements and lack heavy rare earth elements. All these data indicate that both the Machangjing alkali-rich porphyry and MME are related to the mantle basaltic underplating，which led to different magma mixing. The formation of the Machangqing porphyry copper-moly deposit is related with such magma mixing. |
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |
