再搬运红粘土的发现及地质意义  

Discovery and Geological Significance of Red Clay in the Liulin Section in the West Part of Lüliang Mountains

作　　者：李建星[1,2] 岳乐平[1] 徐永[1] 孙勃[1] 孙蕗[1] 王晓勇[2] 白斌[1,3] 

机构地区：[1]西北大学大陆动力学国家重点实验室,西安710069 [2]中国地质调查局西安地质调查中心,西安710054 [3]中国石油勘探开发研究院,北京100086

出　　处：《沉积学报》2009年第6期1184-1190,共7页Acta Sedimentologica Sinica

基　　金：国家重点基础研究发展计划项目(编号:2003CB214607);教育部长江学者和"油气盆地"创新团队发展计划项目(编号:IRT0559);国家自然科学基金项目(批准号:40372202);中国科学院黄土与第四纪地质国家重点实验室开放基金项目(批准号:SKLLQG0511);中国地质调查局项目(编号:20022307;1212010610313)共同资助

摘　　要：在位于吕梁山西部山前山西柳林卫家洼红粘土层下部发现了一套特殊的水成砂砾层,组成该砂砾石层的碎屑主要是红粘土团块及钙质结核。沉积学的研究表明红粘土和钙质结核碎屑具有不同程度分选性和磨圆度,作为碎屑的钙质结核不再具有不规则的"生姜"状外形而呈典型的圆状或次圆状,这是经过搬运碎屑的典型特征。垂向上自下向上变细的沉积序列,部分层位中埋藏有动物化石都是典型水成堆积物的特征。磁性地层学研究表明其形成于8M a前。这种特殊水成堆积物的发现可为红粘土的成因解释提供新资料。A special aqueous gravel bed, which underlies the red clay and is mainly composed of red clay lumps and calcium nodules, was found at Weijiawa village of Liulin county in the west part of Lǔliang Mountains. Sedimentological study shows that the clast（ composed of the red clay and calcium nodule） in this bed are all with certain sorting and roundness, The calcium nodules did not show the anomalous ginger shape but process typical round or sub-round character, which is the product of fluviatile transport. Both sedimentary sequence＇s fining upward and fossil in certain beds are all typical features of aqueous deposit. The clast （ red clay and calcium nodule） in the section indicate that some red clay deposited before the aqueous sediments. Magnetostratigraphic result reveals that the aqueous gravel bed is aged about 8.1 Ma. The discovery of the special aqueous gravel bed can provide new information for the cause of red clay.

关 键 词：红粘土 古地磁测年 吕梁山 柳林 

分 类 号：P512.2[天文地球—地质学]