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风火山群为青藏高原北部羌塘、可可西里地区的一套红层,因沉积环境及岩性等因素,其化石发现非常稀少,关于其时代有各种不同看法,影响了青藏高原地质过程的正确重建.本文从青海省南部风火山北坡该群上部层位的2块样品中发现了丰富的孢粉化石,其时代可以明确地限定为晚白垩世晚期即?晚Campanian至Maastrichtian.结合前人的化石记录,推测整个风火山群的沉积时代可能为早白垩世晚期(?Albian)至Maastrichtian.当前风火山群孢粉植物群以被子植物花粉为主,裸子植物花粉和蕨类、苔藓类孢子次之,且麻黄类及与杉科、柏科有关的花粉在组合中含量突出,指示当时的气候温暖、干旱,是一种亚热带森林-灌丛植被景观.
The Fenghuoshan Group is a set of red beds in the Qiangtang and Hoh Xil area in the northern part of the Qinghai-Tibet Plateau. Due to the sedimentary environment and lithology, the Fenghuoshan Group has very few fossil discoveries and various views on its age, affecting the correct reconstruction of the Qinghai-Tibet Plateau’s geological processes In this paper, abundant sporo-pollen fossils were found in two samples from the upper part of the north of Fenghuoshan Mountain in southern Qinghai Province, whose age can be clearly defined as Campanian to Maastrichtian in Late Late Cretaceous. The fossil record suggests that the whole Eocene volcanic assemblage may be from Albian to Maastrichtian in the Early Cretaceous. At present, the volcanic flora of Fenghuoshan is dominated by pollen of angiosperms, pollen and ferns of gymnosperms, The ephedra and the pollens related to Cedrus and Platycodon were prominent in the assemblage, indicating that the climate was warm and arid at the time. It was a subtropical forest - shrub vegetation landscape.