摘要
通过对宾县鸟河乡鸟河剖面和红石山剖面的沉积学分析,结合古生物、地球化学和古地理位置等资料,初步恢复了当时的古环境特征。鸟河剖面以灰绿色泥岩为主,夹有黄铁矿和白云岩结核层,属于湖湾环境沉积;红石山剖面下部以绿色泥岩为主,中上部变为以红色泥岩为主的沉积,早期属滨浅湖环境,之后水体变浅逐步转为泥坪相沉积。当物源不充足时,沉积物以泥岩为主,发育水平层理,化石种类少但成层性好,泥岩中常夹有白云岩和黄铁矿层。湖湾从湖盆断裂坳陷开始,经水体加深接受沉积,水流波浪侵蚀破坏湖底及湖岸阻隔,后水体逐步变浅,最终转化为泥沼。
Through the sedimentologic analysis of Niaohe and Hongshishan sections in Niaohe village of Binxian,combined with the information of paleontology,geochemistry and paleogeography,the authors restored paleoenvironment characteristics preliminarily. In the Niaohe section,the strata mainly consist of gray-green mudstone with pyrite and dolomitic tuberculosis layers,belonging to lake bay environmental deposit. In the bottom of Hongshishan section,the strate are mainly composed gray-green mudstone,changed to red mudstone in top and middle part,belonging to shallow lake at early stage,gradually turned to mud-flat deposit. The sediments were mainly mudstone and developed horizontal bedding when the provenance was not sufficient; yielding less fossils,but the layered property was good; there were dolostone and pyrite in mudstone. The lake bay accepted deposition by water deepening from the fracture depression of lake basin,and water flow or wave erosion damaged the barrier in lake bottom and lakeshore which led to water shallowed and turned to slough finally.
出处
《世界地质》
CAS
CSCD
2010年第2期262-270,共9页
World Geology
基金
国家重点基础研究发展规划项目(G2006CB701403)
关键词
松辽盆地
宾县
青山口组
沉积相
湖湾
Songliao Basin
Binxian
Qingshankou Formation
sedimentary facies
lake bay
