Palynological assemblages and paleoenvironmental evolution in the Gyirong Basin since Middle Miocene
The formation and evolution of the Himalaya orogeny,resulted from the collision between the Indian and Eurasian plates,has long captivated researchers in earth and life sciences.Late Cenozoic fluvio-lacustrine sedimentary basins,distributed along the Southern Tibet Detachment System on the northern slope of the Himalaya,have documented the evolution of the orogeny and paleoenvironmental changes.This study presents palynological analysis on the Danzengzhukang Formation,Woma Formation and Gongba Formation in the Gyirong Basin in the central Himalaya,to explore the sedimentary stratigraphy of the basin and the processes of Himalaya uplift and environmental effects.Based on palynological analysis,the deposition age of the Danzengzhukang Formation is revised to the Middle Miocene.Palynological assemblages reveal that since Middle Miocene,vegetation in the Gyirong Basin has transitioned from a mixed coniferous and broad-leaved forest to sparse woodlands and grasslands in Late Miocene.Subsequently,during the late Late Miocene and Pliocene,it evolved into alpine meadows,eventually forming the present-day alpine shrub and meadow vegetation since the Early Pleistocene.Paleoelevation analysis results indicate that the elevation of the Gyirong Basin has remained relatively similar to the present elevation since Middle Miocene,with no significant uplift during the deposition of the Danzengzhukang Formation and Woma Formation.
NETL
NSTL
万方数据
维普
