地质学报2024，Vol.98Issue(1)：200-213,14.DOI:10.19762/j.cnki.dizhixuebao.2023303
鄂尔多斯盆地盐池地区延安组孢粉组合的发现及其古气候意义
Discovery of sporopollen assemblages of Yan'an Formation in Yanchi,Ordos basin,and its paleoclimate significances
摘要
Abstract
For rebuilding the paleoclimate and paleoenvironment during the early-middle Jurassic in the Yanchi area of the Ordos basin,we analysis the palynological characteristics and clay minerals of the core Ningdong-2,sporopollen assemblages and sporopollen spectra were established.The lower part of the Yan'an Formation is the Inaperturopollenites-Psophosphaera-Protopinus assemblage,whose age is the late Toarcian of Early Jurassic.The upper part of this formation is the Cyathidites-Deltoidospora-Cycadopitees assemblage,whose age is early Middle Jurassic.The boundary of lower and middle Jurassic is located between 2144.5～2153.0 m of the core.The paleoclimate and paleovegetation established by pollen spectrum shows that the late Toarcian of early Jurassic period was a warm temperate semi-humid climate whose vegetation type was coniferous forest.The early Middle Jurassic was generally subtropical humid climate,whose vegetation appearance transformed from coniferous broadleaf mixed forest-grass type to the coniferous forest-dilute grass type.From the late Toarcian of Early Jurassic period to the early Middle Jurassic period,the humidity changed from semi-humid to wet while the temperature changed from low to high.This climate change trend was also found in clay minerals analysis.The climate shift has had a clear role in promoting coal gathering in the region.关键词
鄂尔多斯盆地/延安组/孢粉组合/黏土矿物/古气候Key words
Ordos basin/Yan'an Formation/sporopollen assemblage/clay minerals/paleoclimate引用本文复制引用
何发岐,张森,姜志超,杨兵,袁琼,巩雪娇,郭彩清,曹晶..鄂尔多斯盆地盐池地区延安组孢粉组合的发现及其古气候意义[J].地质学报,2024,98(1):200-213,14.基金项目
本文为中石化项目(编号34550000-2-FW2099-0055)和科技部项目(编号2022FY101800,2022FY101801)联合资助的成果. （编号34550000-2-FW2099-0055）
