鄂尔多斯盆地下侏罗统富县组孢粉植物群对Jenkyns事件的响应  

Palynoflora from the lower Jurassic Fuxian Formation in Ordos basin and its response to the Jenkyns event

作　　者：韦一 南青民 杨兵 张新智 孙思远 苏桂芬 WEI Yi;NAN Qingmin;YANG Bing;ZHANG Xinzhi;SUN Siyuan;SU Guifen(School of Safety Engineering,North China Institute of Science and Technology,Langfang,Hebei 065201,China;Cores and Samples Center of Natural Resources,China Geological Survey,Langfang,Hebei 065201,China)

机构地区：[1]华北科技学院安全工程学院,河北廊坊065201 [2]自然资源实物地质资料中心,河北廊坊065201

出　　处：《地质学报》2024年第10期3017-3030,共14页Acta Geologica Sinica

基　　金：中央高校基本科研业务费(3142018004);国家自然科学基金(编号41702366);中石化项目鄂尔多斯盆地钻孔层型集成柱——鄂尔多斯盆地“铁柱子”的研究项目(编号34550000-21-FW2099-0055);中国地质调查局项目实物地质资料采集更新与数字化应用项目(编号DD20230138)联合资助的成果。

摘　　要：为研究Jenkyns事件对内陆盆地古气候的影响,通过对鄂尔多斯盆地南部富县组孢粉鉴定、分析,划分出3个孢粉组合,由下至上:①Cyathidites-Deltoidospora-Chasmatosporites组合,地质年代为早侏罗世普林斯巴期;②Classopollis-Quadraeculina-Chasmatosporites组合,地质时代为早侏罗世托阿尔期早—中期,与Jenkyns事件发生的时间一致;③Cyathidites-Cycadopites-Psophosphaera组合,地质时代为早侏罗世托阿尔期晚期。孢粉群落反映的古气候信息显示:早侏罗世鄂尔多斯盆地经历了由亚热带湿润性气候→亚热带半湿润半干旱型气候→亚热带湿润性气候的转变。与前人在特提斯洋和泛大洋区域研究所得出的结论不同的是,Jenkyns事件在鄂尔多斯盆地(亚欧大陆腹地)表现为趋干趋热事件。For researching the influence of Jenkyns event on the paleoclimate of inland basins,we analysis the palynological characteristics of Fuxian Formation in the southern Ordos basin.Three palynological assemblage were divided from bottom to top as:Cyathidites-Deltoidospora-Chasmatosporites assemblage,whose age is the Pliensbachian of early Jurassic;Classopollis-Quadraeculina-Chasmatosporites assemblage,whose age is the early-mid Toarcian of the early Jurassic,which coincides with the Jenkyns event;Cyathidites-Cycadopites-Psophosphaera assemblage whose age is the late Toarcian of early Jurassic.The paleoclimate reflected by sporopollen community shows that the Ordos basin experienced the transformation as subtropical humid climate→subtropical semi-humid and semi-arid climate→subtropical humid climate during the early Jurassic Fuxian period.Different from the previous conclusions of the Tethys Oceanic and Pan-Oceanic studies,the Jenkyns event appears as a drying and heating event in the Ordos basin(the hinterland of Eurasia).

关 键 词：托阿尔期 富县组 孢粉 Jenkyns事件 鄂尔多斯盆地 

分 类 号：P618.13[天文地球—矿床学]