Geological Record of Paleo-and Mesoproterozoic Orogenesis in the Western Margin of Upper Yangtze Block
详细信息
- 责任者：Yin Fuguang (Chengdu Institute of Geology and Mineral Resources ; Chengdu 610081 ; China) ; Sun Zhiming
- 刊名：Acta Geologica Sinica
- 出版年：2012
- 卷期：86(12)
- 关键词：造山运动 ; orogeny ; 扬子地区 ; Yangtze Region
- 页码：p.1917-1932
- 图表：7 illus., 3 tables, 57 refs.
- 分类号：0300
- issnNo：ISSN0001-5717
- isbnNo：CN11-1951/P
摘要
///During Paleo-and Mesoroterozoic epochs, three sets of low metamorphism sedimentary and volcanic successions represented by the Hekou Gr., Dahongshan Gr., Dongchuan Gr., Kunyang Gr. And Huili Gr. were developed within the southwestern margin of upper Yangtze block. Along with sedimentary facies, major, trace and rare earth elements chemical data indicate that the southwestern margin of the upper Yangtze block experienced four development stages during Paleo-and Mesoproterozoic. At ca. 1 800～1 600 Ma, a near EW-trending rift basin was developed within the Dahongshan, Hekou, and Dongchuan areas. At ca. 1 600～1 300 Ma, the Dongchuan area was in a passive continental extensional setting. At ca. 1300~1100Ma, the Caiziyuan-Matang areas were the intraplate rift-oceanic basin while the Laowushan area was a rifting basin. At ca.1 100～1 000 Ma, the Caiziyuan-Matang rift-ceanic basin subducted northward or both northward and southward to form volcanic arc in Tianbaoshan and Fulingpen areas. Meanwhile, orogensis- or collision-type granite was formed in the western margin of the Yangtze at ca. 1.0 Ga (1 007±14～1 014±8 Ma). All this evidence indicates that Sichuan Province and Yunnan Province had jointed together, which, along with the whole upper Yangtze block, formed the Rodinia supercontinent.