Oligocene-Pliocene Sedimentary Facies Analysis and Sedimentary Evolution of Xunhua Basin in Northeastern Margin of Qinghai-Tibet Plateau

• 责任者：Zhang Jianyu (Key Laboratory of Biogeology and Environmental Geology ; Ministry of Education ; China University of Geosciences ; Wuhan 430074 ; China) ; Zhang Kexin
• 刊名：Earth Science
• 出版年：2010
• 卷期：35(5)
• 关键词：沉积相 ; sedimentary facies ; 沉积演化 ; sedimentary evolution ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.774-788
• 图表：9 illus., 35 refs.
• 分类号：08803
• issnNo：ISSN1000-2383
• isbnNo：CN42-1233/P

 The measured section in the southern margin of Xunhua basin located at Yangjuangongbai-Xigoushangzhuang Village, Jishi Town, Xunhua County, Qinghai Province, consists of Miocene to Pliocene strata, named as Tala Fm., Xianshuihe Fm. and Linxia Fm. The detailed research of sedimentary facies indicates that the depositional system of the section consists of alluvial fan facies, salt water lacustrine facies and delta front facies, lacustrine facies and delta front facies with underwater fan facies from bottom to top. Paleocurrent measurements obtained from the structures and cross-beddings show that the paleocurrent direction of section was SE-NW, except the Linxia Fm. The sedimentary origin analysis demonstrates that the northern margin of the western Qinling thrust belt and the south margin of the Lajishan thrust belt had uplifted as denudation areas and provided deposits to the Xunhua Basin.