| 湖北秭归吴家坪组—长兴组界线氧化还原条件及其意义 |
| |
| 引用本文： | 张璇,韦恒叶.湖北秭归吴家坪组—长兴组界线氧化还原条件及其意义[J].沉积学报,2020,38(3):476-484. |
| |
| 作者姓名： | 张璇 韦恒叶 |
| |
| 作者单位： | 东华理工大学地球科学学院, 南昌 330013 |
| |
| 基金项目： | 国家自然科学基金项目41762003 |
| |
| 摘 要： | 二叠纪发生了两次重大生物灭绝事件,一次是位于吴家坪初期即瓜德鲁普世末生物灭绝事件,另一次是位于长兴末期即晚二叠世末生物灭绝事件。在这两次生物灭绝事件之间的大约八百万年时间里,其环境变化研究相对较少,古海洋的氧化还原条件变化目前尚未清楚。通过分析湖北秭归县杨林剖面的黄铁矿形态来探讨吴家坪组—长兴组界线氧化还原条件及其意义。研究结果表明:吴家坪组与长兴组石灰岩沉积时期的古海水主要是贫氧至氧化环境。在吴家坪组上部至长兴组下部地层沉积时期古水体出现间歇性硫化现象。该硫化缺氧事件不仅出现在秭归地区,还广泛分布于鄂西盆地、扬子台地南缘南盘江盆地、阿拉伯地台以及东格陵兰盆地地区。这说明吴家坪—长兴组界线沉积时期的间歇性硫化缺氧事件有可能是一个全球性事件。该事件可能与二叠末事件有一定的关联。
|
| 关 键 词： | 吴家坪组 长兴组 草莓状黄铁矿 氧化还原条件 秭归 |
| 收稿时间： | 2019-11-26 |
Redox Conditions and their Implications at the Wujiaping-Changxing Formation Boundary in Zigui,Hubei Province |
| |
| ZHANG Xuan,WEI HengYe.Redox Conditions and their Implications at the Wujiaping-Changxing Formation Boundary in Zigui,Hubei Province[J].Acta Sedimentologica Sinica,2020,38(3):476-484. |
| |
| Authors: | ZHANG Xuan WEI HengYe |
| |
| Institution: | School of Earth Sciences, East China University of Technology, Nanchang 330013, China |
| |
| Abstract: | Two mass extinctions occurred in the Permian, one at the beginning of the Wujiapingian, the extinction at the end of the Guadalupian, and the other at the end of the Changxingian, the end-Permian extinction. During the eight million years between the two extinctions, environmental changes have attracted few studies, and the paleoocean redox conditions are still unclear. This study analyzed pyrite morphology and framboid size distribution across the boundary of the Wujiaping and Changxing Formations at Yanglin in Zigui county, Hubei province, and discusses the redox conditions. The results show that the conditions of the water column during the deposition of carbonates in the Wujiaping and Changxing Formations were mainly dysoxic-oxic. Episodic euxinia occurred from the upper Wujiaping to the lower Changxing formations. The euxinic events at the Wujiapingian-Changxingian boundary occurred not only at Zigui, but also in other locations in the West Hubei Basin, the Nanpanjiang Basin in the southern Yangtze Platform, the Arabia margin and in East Greenland, implying a global event. This euxinic event may be linked to the Late Permian event. |
| |
| Keywords: | Wujiaping Formation Changxing Formation framboidal pyrite redox conditons Zigui |
| 本文献已被 CNKI 维普 等数据库收录！ |
| 点击此处可从《沉积学报》浏览原始摘要信息 |
| 点击此处可从《沉积学报》下载免费的PDF全文 |
|
