松辽盆地白垩系青山口阶缺氧事件层的有机地球化学特征  

Organic geochemical characteristics of anoxic levels in the Cretaceous Qingshankou Formation of Songliao Basin

作　　者：孔惠[1] 黄永建[2] 黄清华[1] 张文婧[1] 谢磊[3] 刘学红[4] 谢晓云[1] 

机构地区：[1]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [2]中国地质大学(北京)青藏高原地质研究中心,北京100083 [3]大庆油田有限责任公司大庆钻探工程公司地质录井一公司,黑龙江大庆163411 [4]大庆油田有限责任公司第一采油厂,黑龙江大庆163162

出　　处：《地学前缘》2009年第6期96-103,共8页Earth Science Frontiers

基　　金：国家重点基础研究发展计划"973"项目(2006CB701403);国家自然科学基金项目(40802012)

摘　　要：松辽盆地白垩系青山口阶下部广泛分布一套富含有机碳的黑色泥岩、页岩沉积,它具有干酪根碳同位素正偏、重排甾烷含量低,普遍存在伽马蜡烷生物标志化合物等有机地球化学特征,代表了白垩纪温室效应时间窗内古湖泊贫氧环境条件下的沉积产物。结合生物地层研究成果,认为青山口阶下部曾发生过古湖泊缺氧事件,其层位大体可与白垩纪古海洋Cenomanian-Turonian界线事件层进行对比,由此提出了松辽盆地青山口阶下部的时代归属于晚白垩世Cenomanian晚期—Turonian早期的新观点。The Songliao Basin was a big lake during the mid-Cretaceous,where dark mudstones and shales of the Qingshankou Formation were distributed in the basin.The dark mudstones and shales in the Member 1 of the Qingshankou Formation are of high organic carbon and low diasteranes contents.Organic geochemical characteristics are illustrated by biomarkers of 28-,30-bisnorhopane and gammacerane,and positive excursion of kerogen isotopes.It is suggested that the dark mudstones and shales in the Member 1 of the Qingshankou Formation are the products of lake anoxic event in the extreme greenhouse climate period.Based on the study of biostratigraphy and anoxic event-stratigraphy,we propose that the Qingshankou Formation may correspond to the oceanic anoxic event at the Cenomanian-Turonian boundary in the Cretaceous,and the age of the Qingshankou Formation in the Songliao Basin is the Late Cenomanian to the Early Turonian.

关 键 词：黑色页岩 碳同位素 生物标志物 缺氧事件 青山口组 白垩系 松辽盆地 

分 类 号：P593[天文地球—地球化学] P534.53[天文地球—地质学]