南羌塘地块民卓茶卡地区2号剖面化石鉴定单

科考人员详细测量了位于西藏阿里地区民卓茶卡北岸的系列剖面，并采集和研究了其中的各门类化石（包括牙形类、蜓类、小有孔虫类）。牙形类以Sweetognathus, Mesogondolella等分子组成，蜓类主要有Neoschwagerina, Pseudodoliolina, Mesoschubertella等，小有孔虫类主要有Pachyphloia, Langella, Palaeotextularia, Tetrataxis等组成。从牙形来看，该牙形动物群的时代相当于早二叠世空谷晚期；从蜓类来看，它的时代是Murgabian期。因此，从年代地层上来看，国际地层标准空谷晚期相当于特提斯标准的Murgabian底界。从古生物地理上来看，当前剖面中的蜓类和牙形类都是以暖水动物群为主，但此时拉萨地块上的空谷期地层中都是以凉水动物群为主。因此，这些动物群的发现表明南羌塘地块和拉萨地块在空谷期时古生物地理完全不同。

Researchers conducted detailed measurements of a series of sections located on the northern bank of Minzhuo Caka, Ngari Prefecture, Tibet, and collected and studied various fossil groups including conodonts, fusulinids, and small foraminifera. The conodont assemblage is composed of taxa such as *Sweetognathus*, *Mesogondolella*, etc.; the fusulinid assemblage mainly includes *Neoschwagerina*, *Pseudodoliolina*, *Mesoschubertella*, etc.; and the small foraminiferal assemblage primarily consists of *Pachyphloia*, *Langella*, *Palaeotextularia*, *Tetrataxis*, etc. Based on conodonts, the age of this conodont fauna corresponds to the late Kungurian stage of the Early Permian; based on fusulinids, its age belongs to the Murgabian Stage. Accordingly, in terms of chronostratigraphy, the late Kungurian stage of the international stratigraphic standard corresponds to the basal boundary of the Murgabian Stage in the Tethyan stratigraphic standard. From the perspective of paleobiogeography, both the fusulinid and conodont faunas in the current sections are dominated by warm-water faunas, whereas the Kungurian strata in the Lhasa Block at that time were dominated by cold-water faunas. Accordingly, the discovery of these faunas indicates that the southern Qiangtang Block and the Lhasa Block had completely distinct paleobiogeographic characteristics during the Kungurian stage.

搜集汇总

背景与挑战

背景概述

该数据集为南羌塘地块民卓茶卡地区2号剖面的二叠纪化石鉴定单，包含牙形类、蜓类和小有孔虫类等化石的详细记录，数据时间范围为278-273百万年（早二叠世空谷晚期）。其关键科学意义在于揭示了该剖面化石群以暖水动物为主，与同期拉萨地块的凉水动物群形成对比，表明南羌塘地块与拉萨地块在空谷期具有不同的古生物地理特征。