松辽盆地南部哈达山附近青山口组二、三段泥岩的岩石学与地球化学特征  

Petrological and geochemical characteristics of mudstone from the 2nd and 3rd Members of Qingshankou Formation near Hada Mountain in southern Songliao Basin

作　　者：孙潇[1] 刘立[1] 刘娜[1] 明晓冉[1] SUN Xiao LIU Li LIU Na MING Xiao-ran(College of Earth Sciences, Jilin University, Changchun 130061, China)

机构地区：[1]吉林大学地球科学学院,长春130061

出　　处：《世界地质》2017年第2期333-345,共13页World Geology

基　　金：国家自然科学基金项目(41172091)

摘　　要：以松辽盆地哈达山青山口组二、三段泥岩盖层为研究对象,通过岩石学和地球化学相结合的方法,对泥岩样品中常量元素和稀土微量元素特征进行了研究,结果表明:(1)泥岩稀土元素(∑REE)总量较高(104.99×10^(-6)~281.88×10^(-6)),∑LREE/HREE比值较高(6.50~9.96),REE配分模式显示轻稀土元素富集而重稀土元素亏损,Eu(0.88~1.16)存在负异常等特征;(2)物源区母岩类型主要为沉积岩和中基性火山岩,源岩的钾交代作用成因可能为黏土矿物中的伊蒙混层转化为自生伊利石;(3)物源区泥岩修正后的CIA值(44.75~72.24)较低,暗示物源区经历了弱风化作用,Sr/Cu指标显示物源区长期受干热型气候控制。Taking the mudstone cap rocks in the 2nd and 3rd Members of Qingshankou Formation in Hada Mountain of Songliao Basin as an example, the authors studied the major elements and trace elements of rare earths in mudstone samples by combining the petrological and geochemical methods. The results show that ：①Mudstone has high amount of rare earth elements （104. 99 × 10^-6 ？281. 88 ×10^-6） , high ∑ LREE/HREE ratio （6. 50-9. 96） , and REE distribution patterns show enrichment in light rare earth elements and depletion in heavy rareearth element, with negative Eu anomaly （0.88-1.16） ; ②Source rock types are mainly sedimentary rocks and intermediate-basic volcanic rocks, the origin of potassium metasomatism of source rocks is likely related to the con-version of clay minerals from mixed-layer illite/smectite to authigenic illite;③The revised CIA value （44. 75-72. 24） of provenance mudstone is low, suggesting that the provenance experienced weak weathering, and Sr/Cu value indicates that provenance was controlled by dry and hot climate for a long time.

关 键 词：松辽盆地 泥岩盖层 矿物组成 风化作用 物源区 

分 类 号：P588.22[天文地球—岩石学] P595[天文地球—地质学]