| 云南罗平中三叠统关岭组沉积环境演化及化石埋藏 |
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| 引用本文： | 马志鑫,张启跃,文芠,胡世学,周长勇,黄金元,丁仲昭.云南罗平中三叠统关岭组沉积环境演化及化石埋藏[J].地球科学,2020,45(8):3104-3118. |
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| 作者姓名： | 马志鑫 张启跃 文芠 胡世学 周长勇 黄金元 丁仲昭 |
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| 作者单位： | 1.中国地质调查局成都地质调查中心, 四川成都 610081 |
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| 基金项目： | 中国地质调查局项目DD20190054国家自然科学基金项目41772022国家自然科学基金项目41661134047 |
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| 摘 要： | 罗平生物群是继二叠纪末全球生物大灭绝后海洋生态系统全面复苏的典型代表.为了更全面地认识罗平生物群产出的沉积环境，通过露头观察、微相分析等方法对云南省罗平县宜石打剖面中三叠统关岭组二段进行了研究，共识别出开阔台地、局限台地（泻湖）、潮坪、台盆、台内滩5种沉积相类型.台内滩的颗粒类型以似球粒、包粒为主，其次为少量鲕粒、生物碎屑，颗粒之间主要为亮晶胶结，局部含少量灰泥，滩体规模较小，指示中等水能量环境，且由下向上具多期发育特征.综合研究表明，中三叠世安尼期Pelsonian亚期早期发生了全球性的海平面上升，导致沉积环境水深迅速增加.研究区沉积相从潮坪相迅速转变为台内盆地相，其相对低能缺氧的环境有利于罗平生物群化石的保存.
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| 关 键 词： | 罗平生物群 关岭组 沉积环境 化石 云南 沉积学 |
| 收稿时间： | 2020-03-12 |
Sedimentary Environment Evolution and Fossil Taphonomic Implications of Middle Triassic Guanling Formation in Luoping,Yunnan Province |
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| Abstract: | The Luoping Biota is typical of the full recovery of the marine ecosystem after the end-Permian mass extinction. In order to more fully understand the sedimentary environment background of the Luoping Biota, the outcrop observation and microfacies analysis were used to study the sedimentary environment of Member Ⅱ of the Middle Triassic Guanling Formation in the Yishida section of Luoping County, Yunnan Province. Five sedimentary facies types are recognized:open platform, restricted platform (lagoon), tidal flat, intra-platform basin, and intra-platform shoal. Member Ⅱ of the Guanling Formation presents multiple stages of intra-platform shoal. The types of particles in the shoal are mainly composed of peloids and coated particles, followed by a small amount of ooids and biological debris. Intergranular pores are mainly filled with sparry calcite cement and minor carbonate mud. The size of the shoal is small. Based on the results of this study and neighboring areas, it is concluded that there was a large-scaled sea level rise during the Pelsonian substage of the early Anisian, which resulted in a rapid increase in the water depth of the sedimentary environment and the development of intra-platform basins. Its relatively low-energy and anoxic environment facilitates the exceptionally well preservation of the Luoping Biota. |
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