A review of Permian stratigraphy, palaeobiogeography and palaeogeography of the Qinghai-Tibet Plateau
A review of Permian stratigraphy, palaeobiogeography and palaeogeography of the Qinghai-Tibet Plateau
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DOI：
10.1016/j.gr.2012.06.010
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发表时间：
2013-07
影响因子：
6.1
通讯作者：
Yi‐chun Zhang;G. Shi;S. Shen
中科院分区：
文献类型：
--
作者：
Yi‐chun Zhang;G. Shi;S. Shen
根据已发表的文献、作者未发表的数据和野外观测，综合了青藏高原各主要构造块的二叠纪海洋岩石地层、生物地层和动物群组成。从古生物地理上看，青藏高原二叠纪海洋动物群可划分为四个生物省：华夏省、印多拉省、西梅里安省和喜马拉雅省，以及二叠纪部分地区的广阔的南部过渡带。昌都地块显然属于华夏省，因为它的特点是在整个二叠纪期间缺乏冰川沉积物并且以温水动物群为主。西藏南部的羌塘地块、拉萨地块和喜马拉雅特提斯带可划归为苏苏拉纪时期的南过渡带，其特点是双壳类Eurydesma、腕足动物Cimmeriella、Bandoproductus和fusuline Monodiexodina的组合。正如羌塘和拉萨地块所示，从Roadian期到Capitanian期，南过渡带诞生了辛梅里安省，在此期间，其动物区系的特点是冷温水元素的混合，并辅以有限数量的特有类群，如梭状始多双出虫、非梭状有孔虫Shanita-Hemigordiopsis组合和珊瑚Thomasiphyllum。南部过渡带和辛梅里安省的形成和发展被解释为与辛梅里安大陆向北漂移以及冈瓦纳冰川消融导致的全球逐渐变暖密切相关并受其驱动。这些事件的综合影响迫使漂流的冈瓦纳大陆块体周围的气候得到改善，其海洋动物从早西苏拉世时期基本上是冷水的冈瓦纳类型，经过一个过渡阶段，转变为洛平阶时期主要是温水的华夏类型。西藏南部的喜马拉雅特提斯带隶属于喜马拉雅省，从晚瓜达鲁普世到洛平世，以冷水腕足动物和珊瑚的持续出现和优势为特征。昌都地块与羌塘地块的二叠纪沉积序列和动物区系演替都存在显着差异。这表明两个地块之间的龙木错-双湖-澜沧江缝合带很可能代表了西藏古特提斯缝合带的主要分支。西藏地块与滇西邻近地块二叠纪层序和动物区系的比较和对比表明，羌塘地块应与保山地块对齐，而拉萨地块与腾冲地块关系更为密切。对所有主要近冈瓦纳地块的二叠纪地层和动物群的进一步比较和关联表明，它们可能构成了三个不同的大陆切片，而不是像以前的一些文献中所认为的那样。第一片由中部帕米尔高原、羌塘地块和保山地块组成；第二部分包括南帕米尔、喀喇昆仑、阿富汗南部、伊朗中部和土耳其。这两个大陆片的特点都是从阿廷斯基期到瓜达卢普期持续活跃的裂谷事件。相比之下，第三个切片被解释为由拉萨地块、腾冲地块和斯布马苏地块组成，其中没有一个地块含有与晚苏拉尔期裂谷相关的玄武岩。保山地块和拉萨地块被认为最初（早期的西苏拉利亚）可能在靠近西澳大利亚的三重交汇点相交，并且……
The Permian marine lithostratigraphy, biostratigraphy and faunal compositions among all the major tectonic blocks in the Qinghai–Tibet Plateau are synthesised based on published literature, authors' unpublished data and field observations. Palaeobiogeographically, the Permian marine faunas in the Qinghai–Tibet Plateau can be assigned to four biotic provinces: Cathaysian, Indoralian, Cimmerian and Himalayan provinces, as well as a broad South Transitional Zone for parts of the Permian. The Qamdo Block clearly belongs to the Cathaysian province as it is characterised by a lack of glacial deposits and a dominance of warm-water faunas during the whole Permian. The Qiangtang Block, Lhasa Block and the Himalaya Tethys Zone in southern Tibet can be grouped into the South Transitional Zone during the Cisuralian, which is characterised by the combination of the bivalve Eurydesma, the brachiopods Cimmeriella, Bandoproductus and the fusuline Monodiexodina. The South Transitional Zone gave birth to the Cimmerian province, as shown in the Qiangtang and Lhasa blocks, from Roadian to Capitanian, during which its faunas were characterised by an admixture of cold- and warm-water elements supplemented by a limited number of endemic taxa such as the fusuline Eopolydiexodina, the non-fusuline foraminifer Shanita-Hemigordiopsis assemblage and the coral Thomasiphyllum. The formation and development of the South Transitional Zone and the Cimmerian province is interpreted to be closely linked to and driven by the northward drift of the Cimmerian Continent superimposed with a gradual global warming in the wake of Gondwanan deglaciation. The consequently combined effects of these events forced the climate of the drifting peri-Gondwana blocks to ameliorate and its marine faunas to transform from an essentially cold-water Gondwanan type in the Early Cisuralian through a transitional stage to a predominantly warm-water Cathaysian type by the Lopingian. The Himayala Tethys Zone in southern Tibet is assigned to the Himalayan province from Late Guadalupian to Lopingian and identified by persistent occurrences and dominance of cold-water brachiopods and corals. Both the Permian sedimentary sequences and faunal successions are strongly different between the Qamdo Block and the Qiangtang Block. This is taken to suggest that the Longmu Co-Shuanghu-Lancangjiang suture between the two blocks most likely represents the main branch of the Palaeotethys suture in Tibet. A comparison and correlation of Permian sequences and faunas between Tibetan blocks and adjacent blocks in western Yunnan indicates that the Qiangtang Block should be aligned with the Baoshan Block whereas the Lhasa Block more closely related to the Tengchong Block. Further comparison and correlations of Permian stratigraphy and faunas of all major peri-Gondwana blocks suggest that they probably constituted three different continental slices, rather than one as perceived in some previous literature. The first slice is composed of Central Pamir, the Qiangtang Block and the Baoshan Block; the second slice consists of South Pamir, Karakorum, South Afghanistan, Central Iran and Turkey. These two continental slices are both characterised by a continuously active rifting event from Artinskian to Guadalupian. By contrast, the third slice is interpreted to consist of the Lhasa Block, the Tengchong Block and the Sibumasu Block, none of which has late Cisuralian rift-related basalts. The Baoshan Block and the Lhasa Block are thought to have initially (early Cisuralian) intersected probably at a triple junction point close to western Australia, and were …