摘要
滇东曲靖—盘溪地区中泥盆统发育良好,可见含丰富生物化石的海相及非海相地层,其中华宁盘溪剖面是中国泥盆纪地层和古生物研究的经典剖面。但是,由于各剖面出露情况和生物群研究程度不同,以及岩相差异和沉积相变等,各岩石地层单元的划分和对比存在较多分歧,生物地层分辨率亟待提高。作者调查了曲靖和盘溪周边的中泥盆统,实测曲靖五台山剖面、东山剖面和华宁盘溪剖面,对比该区中泥盆统浅海相岩石地层单元,厘定华宁组、曲靖组和婆兮组的同物异名和异物同名现象及其有效性。根据岩相和生物组合对比,明确盘溪—曲靖地区的所谓“海口组砂岩”与陆相“海口组”含义不同。盘溪剖面“海口组”的使用不符合地层命名规范,它与曲靖五台山、东山剖面曲靖组所含砂岩层均代表滨海碎屑岩向浅海相碳酸盐岩过渡的交替沉积。
Panxi and Qujing areas of eastern Yunnan are renowned for their well-developed Middle Devonian strata,containing abundant benthic faunas. The Panxi section in Huaning County represents one of the most classical Devonian strata for stratigraphic and paleontological studies. However, correlation among the Devonian sequences in these areas remains controversial, mainly due to limited exposure and discrepancies on the research of the strata, especially in terms of faunal composition, lithofacies, and stratigraphic subdivisions, appealing for high-resolution stratigraphic work. In this study, we review the history and research background of the Devonian sequences in the Qujing and Panxi areas, and evaluate the stratigraphic units(i.e., the Qujing, Huaning, Poxi, Haikou, and Sandaoqing formations, the Nanpanjiang Limestone, etc.) based on detailed investigations on the Dongshan, Wutaishan, and Panxi sections. The validity of the Huaning, Qujing and Poxi formations is discussed in this study according to the nomenclature regulations of lithostratigraphic units. In terms of lithofacies and fossil assemblages, the so-called “Haikou Sandstone” in the Panxi-Qujing area, which is composed of intercalation of siliciclastics and carbonates, is different from that of the originally named “Haikou Formation” that is mainly composed of sandstones. Therefore, it is not suitable to use the “Haikou Formation” at the Panxi section. In fact, both the “Haikou Formation” at the Panxi section and the Qujing Formation containing sandstone intercalations at the Wutaishan and Dongshan sections in Qujing represent a transitional facies from coastal clastic sediments to shallow-marine carbonates.
作者
刘琮滢
乔丽
梁昆
LIU Cong Ying;QIAO Li;LIANG Kun(State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment,Chinese Academy of Sciences,Nanjing 210008;University of Chinese Academyof Sciences,Beijing 100049)
出处
《地层学杂志》
CSCD
北大核心
2022年第4期346-356,共11页
Journal of Stratigraphy
基金
国家自然科学基金(42172025)
中国科学院战略性先导科技专项(XDB26000000)共同资助。
关键词
岩石地层
生物地层
同期异相
曲靖组
海口组
泥盆纪
lithostratigraphy
biostratigraphy
contemporaneous heterotopic facies
Qujing Formation
Haikou Formation
Devonian
