摘要
吐鲁番—哈密盆地托克逊凹陷早侏罗世地层中产孢粉化石共53属74种。通过对纵向上典型属种及优势组分含量变化规律的分析可划分为两个孢粉组合Osmundacidites-Protopinus-Cycadopites组合和Cyathidites-Piceaepollenites-Cycadopites组合,它们分别产自八道湾组和三工河组。根据孢粉组合特征及与国内外有关化石群进行比较,八道湾组的时代应属早侏罗世早期;三工河组的时代应为早侏罗世晚期。托克逊地区当时的植被是由银杏、苏铁类和松柏类等乔木,并伴有真蕨类等草本植物组成。古气候应属亚热带气候。
species of spores and pollen of 53 genera are found in the Lower Jurassic deposits in the Toksun subbasin of the Turpan-Hami basin, northwestern China. Through an analysis of the changes in contents of typical general and species and dominant components, two sporopollen assemblages may be distinguished in ascending order as follows: the Osmundacidites - Protopinus - Cycadopites assemblage and the Cyathidites - Piceaepollenites - Cycadopites assemblage. According to the features of the sporopollen assemblages and comparison of related fossil assemblages in China and abroad, the age of the Badaowan Formation should be early Early Jurassic, and the age of the Sangonghe Formation should be late Early Jurassic. At that time the vegetation of the Toksun area consisted of such arbores as Ginkgo, Cycadopites and Coniferales, associated with herbs such as Filices. The paleoclimate should belong to the subtropical one.
出处
《中国地质》
CAS
CSCD
2004年第2期186-191,共6页
Geology in China
基金
高等学校骨干教师项目()资助。
