摘要
通过对山西宁武陆相二叠系—三叠系剖面的孙家沟组至刘家沟组磁化率的研究,发现该剖面自孙家沟组顶部的粘土岩层至刘家沟组底部,存在着明显的磁化率值升高的现象,认为该现象是由于气温升高和火山事件的影响。对比山西宁武剖面与浙江长兴海相剖面以及贵州威宁陆相剖面二叠系—三叠系界线附近的磁化率研究成果,发现三者具有很好的一致性。这表明,该磁化率值明显升高的现象具有跨区(晋、浙、黔)和跨相(陆、海)的区域性特征,可用于地层的划分和对比。根据磁化率的研究结果,建议将山西宁武剖面的二叠系—三叠系界线设在磁化率值明显升高的地方,即17层顶部纹层粉砂岩之下的粘土岩层。
This paper studies susceptibility characteristic of the terrestrial PermianTriassic section in Ningwu, Shanxi Province.The susceptibility curve shows an outstanding increase from the clay layer in the top of Sunjiagou Formation to the bottom of Liujiagou Formation, and the characteristic results from the increase of the air temperature and the volcanic events. The comparison of the susceptibility characteristics of Ningwu section with the sea facies PermianTriassic section in Meishan, Changxing of Zhejiang Province and the terrestrial PermianTriassic section in Weining, Guizhou Province reveals, remarkable coherence and proves that the susceptibility characteristics are regional and can be used as a sign for the stratigraphic division and correlation. Accordingly, the boundary of PermianTriassic should be located at the point of susceptibility increase, namely the clay layer below the siltstone in the top of the 17th layer.
出处
《地质科技情报》
CAS
CSCD
北大核心
2003年第3期37-40,共4页
Geological Science and Technology Information
基金
中国石油及天然气股份有限公司"十五"重点项目"中国北方油气区石炭系-二叠系划分对比
古环境研究及油气远景评价项目子课题"(016083)
中国地质大学"地质学理科基地班特助基金项目"(2002)
