河南省汝阳盆地早白垩世古气候特征及生物灭绝  

Palaeoclimatic characteristics during the early Cretaceous and mass extinction in the Ruyang Basin of Henan Province

作　　者：徐莉 贾松海 张纪明 吕君昌[2] 张成君[3] 

机构地区：[1]河南省地质博物馆,郑州450016 [2]中国地质科学院地质研究所,国土资源部地层与古生物重点实验室,北京100037 [3]兰州大学地质科学与矿产资源学院,兰州730000

出　　处：《兰州大学学报（自然科学版）》2016年第2期179-187,195,共10页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金项目(41272022);河南省国土资源厅地质矿产科技攻关项目(豫财招标采购2009-61号-8、豫财招标采购2011-622号-2)

摘　　要：通过对汝阳盆地郝岭和曹家沟早白垩统含恐龙化石地层岩性特征描述,以及环境地球化学样品采集和有机碳质量分数、稳定同位素组成、有机碳同位素组成等分析,结果表明研究区地层古环境演变与全球阿普特阶的古环境演变极具相似性.阿普特阶早期气候干旱、中期发生较强的降温过程,恐龙在早-中期的干旱和中期的降温事件中大量灭绝.恐龙化石层中有机质质量分数较低,无机和有机碳同位素组成均有偏重的趋势,代表了该段时期气候干旱少雨、植被不发育的古环境特征,食物的短缺及明显的降温可能是造成恐龙大量灭绝的直接原因之一.We described the characterstics of formation lithology keeping dinosaur bone fossils and collected geochemical samples from the sections in Haoling and Caojiagou.Total orgainc carbon and stable isotopes and organic carbon isotopic compositions had been analysized.The results showed that palaeoenvironmental change in Haoling and Shijiagou of Ruyang Basin had greatly similarity with that of global in the period of Aptian stage.Strong dry palaeocliamte was at the early stage and temperature low event happened at middle stage.Dinosaurs extincted greatly at the early and middle stages under dry and temperature low event conditions.Organic matter in the strata keeping dinosaur bone fossils was low and stable carbon and oxygen isotopes,organic isotopes were heavier.This kind of characteristics indicated that the palaeoclimate was dry and less rainfall to make undeveloped vegetation that time.The food shortage and obvious temperature low event are one of the direct reasons of dinosaur mass extinct.

关 键 词：早白垩世中-晚期 恐龙化石层 古环境 郝岭和曹家沟 河南汝阳盆地 

分 类 号：P588.122[天文地球—岩石学]