• 责任者：Duan Zhiming (Chengdu Institute of Geology and Mineral Resources ; China Geological Survey ; Chengdu 610082 ; China) ; Zhang Yuxiu
• 刊名：Acta Geologica Sinica
• 出版年：2013
• 卷期：87(12)
• 关键词：石英闪长岩 ; quartz diorite ; 岩石地球化学 ; lithogeochemistry ; 西藏 ; Tibet
• 页码：p.1874-1886
• 图表：11 illus., 3 tables, 74 refs.
• 分类号：0801
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

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     quot;EN-US">quot;Calibri" size="3">The Mazicuo quartz diorites is located at southwest of the Xainshuihe fault, southern Songpan-Ganzi Terrane. The quartz diorites demonstrate high potassium quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">3.53%-3.86%quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3">, Ca-rich quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">4.91%-6.07%quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3">, low A1 content quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">14.60%-15.24%, A/CNK=0.80-0.89quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3"> and total rare earth elements quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">REEquot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3">. Light rare earth elements quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">LREEsquot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3"> are enriched but slightly Eu depleted, with whole rock quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">8- Sr/86 Srquot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3">i= 0. 707407 -0. 707640 implying that the Mazicuo magma origined from crust-mantle mixed melting or partial melting of lower crust. The Mazieuo quartz diorites belong to lower crust-remelting I-type high-potassium calc-alkaline granite series. The trace element diagrams for discriminating tectonic environments indicate that the Mazicuo quartz diorites resemble volcanic arc granites. The enrichment in Rb quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">60.1 quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">×quot;EN-US">quot;Calibri" size="3"> 10 6 -85.9 quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">×quot;EN-US">quot;Calibri" size="3">10-6quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3"> andCs quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">4.01quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">×quot;EN-US">quot;Calibri" size="3">10-6-19. 62quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">×quot;EN-US">quot;Calibri" size="3">10-6quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3">, and high K20/Na20 quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">1. 31-1. 82quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3"> ratio suggest that biotite-rich sources are responsible for the Mazicuo magma. The zircon SHRIMP U-Pb age of 221-2.0 Ma quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">（quot;EN-US">quot;Calibri" size="3">MSWD=I. 4quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">）quot;EN-US">quot;Calibri" size="3"> shows the intrusive age is Late Triassic, while the whole-rock Rb-Sr age of 207quot;font-family: 宋体; mso-ascii-font-family: calibri; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 宋体; mso-fareast-theme-font: minor-fareast; mso-hansi-font-family: calibri; mso-hansi-theme-font: minor-latin">quot;3">＋quot;EN-US">quot;Calibri" size="3">2.0 Ma may indicate the quartz diorites uplifted at late Late Triassic. The Mazicuo quartz diorites might form in Late Triassic back-arc tectonic background and derive from crust-mantle mix melting resulting from diapiric uplifting of lithospheric mantle magma.