摘要
华北南缘中元古界熊耳群大古石组为华北克拉通形成后的第一套陆源碎屑岩层,对了解熊耳裂谷盆地早期的沉积环境与熊耳群构造背景具有重要意义。在对济源大古石组典型剖面进行详细实测和采样的基础上,运用沉积学和元素地球化学方法,对豫西济源中元古界大古石组进行沉积环境、物源特征及构造背景研究。结果表明,大古石组为一套由粗碎屑砂岩和泥质碎屑岩组成的河流—辫状河三角洲—湖泊相的淡水沉积层;沉积物离物源较近,具有短距离搬运、快速堆积的特点;物源以长英质为主,岩性为花岗岩类并伴有长英质火山岩成分的参与。通过分析大古石组沉积环境演化及物源示踪,可为研究中元古代早期华北克拉通伸展—裂解事件及与哥伦比亚超大陆聚合—裂解事件响应提供参考。
The Mesoproterozoic Xiong′er group Dagushi Formation was the first set of terrigenous clastic rocks in southern margin of north China,it has the great significance to understand the early sedimentary environment and structural background of the Xiong′er rift basin.Based on detailed actual measurements and sampling of geological section from Dagushi Formation in Jiyuan area.Sedimentology and element geochemical methods are used to study the sedimentary environment and its provenance characteristics as well structual background of the Mesoproterozoic Xiong′er group Dagushi Formation in Jiyuan,western Henan Province.The results showed that the Dagushi Formation is a set of continental fluvial-braided river delta-lacustrine facies freshwater sediments composed of coarse clastic sandstone and argillaceous clastic rock.The sediments are close to the provenance as well have the characteristics of short distance transportation and rapid accumulation.The provenance was mainly composed of felsic,the lithology of provenance are the granitoids as well felsic volcanic rocks are involved.By analyzing of sedimentary environment evolution and provenance trace of the Dagushi Formation can provide reference value to the study of the extension and breakup events of NCC in the early-Mesoproterozoic as well the responses to the extension and rifting events of the Columbia supercontinent.
作者
魏丹峰
Wei Danfeng(Department of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,China)
出处
《能源与环保》
2021年第5期112-118,251,共8页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
关键词
大古石组
沉积学
元素地球化学
沉积环境
物源示踪
Dagushi Formation
sedimentology
element geochemical
sedimentary environment
provenance constrains
