摘要
唐古拉山地区广泛出露早新生代陆相地层,较好地记录了青藏高原北部新生代地质构造演化与古环境变迁的过程。通过在该区1∶25万地质调查对雅西措组上段进行孢粉分析表明,孢粉组合以裸子植物花粉为主要成分,地质时代为早—中渐新世。在此基础上划分了3个孢粉植物群-气候期,当时植被是以松科植物为主组成的针叶林植被,从早期到中期喜湿热的蕨类植物和落叶阔叶树种增多;气候从凉爽湿润的南温带→半湿润偏干的北亚热带→偏干的南温带的转变。
The Cenozoic fluvial strata, exposed widely in the Tanggula Mountains, detaily recorded the information of the uplift of the northern Tibet Plateau and the paleoenvironmental evolution. The palynological analysis was carried out from the upper section of the Yaxicuo Formation during 1 ： 250 000 geological mapping in the Chibzhang Co area, Tanggula Mountains. Palynoflora was characterized by the predominant appearance of gymnospermous elements. The angiospermous pollen and pteridophyte spore increased in ascending order respectively. The upper section of the Yaxicuo Formation refers to early-middle Oligocene. Three palynoflora-climate stages were divided mainly based on the palynological spectrum of the section. In the early-middle Oligocene, the paleovegetation is characterized by predominant Pinaceae of gymnospermous plants, espeacially Abiet, Pinus, Cedrus and Picea. The amount of deciduousbroadleaf plants and pteridophyte plants increased from the early to middle Oligocene, which implies a paleoclimate change from the cool-humid southern temperate zone, northern subtropical semi-humid one to semidry southern temperate one.
出处
《微体古生物学报》
CSCD
北大核心
2008年第2期185-195,共11页
Acta Micropalaeontologica Sinica
基金
中国地质调查局重大基础研究项目(NO1212010610103)
大调查项目(NO200013000009121)
湖北省地球表层系统开放实验室基金项目(NOLESS-0102)资助
关键词
孢粉植物群
古植被和古气候
雅西措组
渐新世
唐古拉山
西藏
palynoflora, paleovegetation and paleoclimate, the Yaxicuo Formation, Oligocene, Tanggula Mountains, Tibet
