摘要
通过对下扬子区泾县、宁国、宜兴等地早三叠世风暴沉积中的粘土矿物进行取样分析,并综合沉积学和古生物学等特征的研究表明:随着K櫣bler指数的增高,所测样品中蒙皂石的含量呈递减趋势,蒙皂石伊利石化明显受阻,并且风暴沉积的各层段粘土矿物组合特征也相差较大,其主要因素是物源的变化。根据沉积特征和粘土矿物组合中蒙皂石和伊利石等含量的不同,可将本次研究的剖面分为两个序列:序列Ⅰ以宁国和宜兴等地为代表,为近源型风暴沉积;序列Ⅱ以泾县为代表,出现了近源和远源的双重属性,究其原因可能是因泾县位于近源和远源沉积的过渡带所致。
Based on sampling analysis of clay minerals on Early Triassic storm deposits outcroped in Jingxian, Ningguo and Yixing in the Lower Yangtze region and integrated sedimentological and paleontologyic studies, it is confirmed that when Kübler index (KI) increase the content of smectite decrease and smectite illitization would be restrained. In addition, the clay mineral associations are distinctly different. Therefore, it is concluded that provenance is the main factor that affects smectite illitization and the difference of clay mineral combination. The sources can be divided into two sequences according to the sedimentological characteristics and the content of smectite and illite in clay mineral combination. The results show that the provenance of storm deposits from profiles of Ningguo and Yixing (sequenceⅠ) are of proximal type, while that of Jingxian profile (sequence Ⅱ) demonstrates a combination of proximal and distal type, which means that the location of Jingxian profile is closer to the transitional zone.
出处
《吉林大学学报(地球科学版)》
EI
CAS
CSCD
北大核心
2010年第4期947-954,共8页
Journal of Jilin University:Earth Science Edition
基金
国家自然科学基金项目(40621063)
关键词
风暴沉积
下扬子区
粘土矿物
物源
近源和远源
沉积物
tempestite
Lower Yangtze region
clay mineral
provenance
proximal and distal
sediments