地质通报2013，Vol.32Issue(1)：141-153,13.
西藏西南部札达盆地新近纪的孢粉组合
Neogene palynological assemblages in Zanda Basin, southwestern Tibet
摘要
Abstract
The Zanda Basin is a Neogene rifted basin in Ngari Prefecture, southwest Tibet. It was formed in Late Miocene, at about 9.2Ma. The Duojidong section is located about 4km south of Zanda County. It has a well-developed set of lacustrine sedimentary strata. Palaeo-current measurement and provenance analysis show that the age interval of the Tuolin Formation is about 9.2-2.6Ma, and the Xiangzi Formation is dated at about 2.6-1.7Ma. As the sporopllen data can direcdy reflect paleoclimate changes, sporopllen data have been always regarded as one of the best environmental indicators. Through the palynological analysis, 6 palynological assemblages and vegetable types were recognized, and 3 phases of paleoclimatic changes were revealed: ① from 9.2Ma to 5.6Ma, correlated with assemblages 1-2, the environment was cold shrub steppe at about 9Ma, and then became warm and humid subtropical-temperate deciduous coniferous and broad-leaved mixed forests; ② from 5.6Ma to 3.1Ma, correlated with assemblages 3-5, the environment was mild and humid evergreen-deciduous broad-leaved mixed forests, and changed to the warm and a litde dry deciduous conifer mixed forest at about 3.6Ma. This stage had a climate fluctuation; ③ from 8Ma to 1.7 Ma, correlatied with assemblage 6, the environment became cold and dry deciduous coniferous and broad-leaved mixed forests and subalpine coniferous forests.关键词
札达盆地/孢粉组合/古气候变化/新近纪Key words
Zanda basin/ palynological assemblage/ paleoclimate change/ Neogene分类
天文与地球科学引用本文复制引用
吴旌,徐亚东,张克信,陈奋宁,陈锐明,陈林..西藏西南部札达盆地新近纪的孢粉组合[J].地质通报,2013,32(1):141-153,13.基金项目
中国地质调查局国家青藏专项《青藏高原新近纪隆升与地质时间群研究》(编号:1212011121261)、国家地质学理科基地人才培养基金项目(批准号:J0830520)和国家自然科学基金项目《国家创新研究群体科学基金》(批准号:40921062)资助 （编号:1212011121261）
