mal style="MARGIN: 0cm 0cm 0pt; mso-pagination: widow-orphan; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-outline-level: 2">man">Zircon SHRIMP Dating and Geochemical Characteristics of Neoproterozoic Granites in Southeastern mas-microsoft-com:office:smarttags" />Hunan Provincemas-microsoft-com:office:office" />

• 责任者：Ma Tieqiu (Hunan Institute of Geological Survey ; Changsha 410011 ; China) ; Chen Lixin
• 刊名：Geology in China
• 出版年：2009
• 卷期：36(1)
• 关键词：花岗岩 ; granite ; 铀—铅计时 ; U-Pb dating ; 湖南 ; Hunan Province
• 页码：p.65-73
• 图表：8 illus., 3 tables，27 refs.
• 分类号：0801
• issnNo：ISSN1000-3657
• isbnNo：CN11-1167/P

mal style="MARGIN: 0cm 0cm 0pt; mso-pagination: widow-orphan; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto">man">There occur Neoproterozoic granitic bodies in Yueyang-Pingjiang area, northeast mas-microsoft-com:office:smarttags" />Hunan Province. Zircon SHRIMP U-Pb dating of the granite from Zhangbangyuan pluton was performed, yielding an age of (816±4.6) Ma. The rocks are lightly basic with an average SiO₂ content of 70.25%, have low potassium and high calcium with an average CaO content of 2.38%, and contain poor alkali with an average Na₂O+K₂O content of 5.97% and the feature Na₂O>K₂O. Geochemical characteristics suggest that the granites are of the island arc volcanic system, and derived their materials from magmatism in the convergent margin of the plate instead of from mantle plume magmatism.