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滇东属于奥陶纪扬子地层区西缘的重要组成部分,本文系统描述该地区奥陶系8个层位的三叶虫,共计10科17属18种(其中包括1个新属种,即Daketia spinata gen.and sp.nov.),初步建立区内的三叶虫动物群地层序列,据此可靠确定有关地层的时代,包括:汤池组(特马豆克晚期—弗洛最早期)、红石崖组(弗洛早期—达瑞威尔最早期)、下巧家组(大坪期—达瑞威尔中期)、上巧家组(达瑞威尔晚期—桑比早期)。典型的红石崖组发育于滇东南部的昆明和宜良一带,其上部为含二叶石砂岩,假整合于泥盆纪石英砂岩之下,但是这部分层段在武定-寻甸一线以北地区并未见及,却沉积了一套砂岩、页岩、泥灰岩和白云质灰岩(即下巧家组);按区内地层发育的时空分布来判断,Zhou等(2011)提出的下巧家组和红石崖组上部应系同期异相沉积的观点得到证实。各地层单元的三叶虫动物群分异度低且均为扬子陆块浅水区的常见地方性分子(包括原来记录于越南北部的Vietnamia douvillei(Mansuy)),指示浅内陆棚环境。
Eastern Yunnan belongs to the western margin of the Ordovician Yangtze stratigraphy. This article systematically describes the Trilobites of the eight Ordovician strata in the area, including 17 species, 17 genera and 10 families (including one new species, namely, Daketia spinata gen.and sp.nov.) To establish the sequence of Trilobites fauna in the area. Based on this, the age of the related stratigraphy can be reliably determined, including the Tangchi Formation (Temasek Late-Early Florian) Hongshiya Formation (Early Floyd - Daruiweier the earliest), under the Qiaojia group (Daping - Daruiweier mid), the Qiaojia group (Daruiweier late - early Sangbi). The typical Hongshiya Formation developed in the areas of Kunming and Yiliang in southeastern Yunnan. The upper part of the Hongshiya Formation is a loam-bearing sandstone that is falsely integrated under Devonian quartz sandstone. However, this part of the layer is located in the area north of Wuding-Xundian But did not see, but deposited a set of sandstone, shale, marl and dolomitic limestone (ie Xia Qiajia Formation); according to the spatial and temporal distribution of stratigraphic development in the area to judge, Zhou et al (2011) proposed The Qiaojia Formation and the upper part of Hongshiya Formation should be confirmed by the contemporaneous heterogeneous deposition. The trilobites fauna in each of the stratigraphic units is low in diversity and is a common endemic molecule (including the original Vietnamia douvillei (Mansuy), originally recorded in northern Vietnam), both of which are indicative of shallow shelf environments.