掸泰地体

掸泰地块，又称掸邦地块、滇缅马苏地块（Sibumasu massif）、滇缅马来亚地块（Sinoburmalaya massif），中国境内称为保山地块。位于缅甸东部掸邦的一个近南北向的长条形地体。北起中国云南保山，向南经过缅甸、泰国、马来半岛，南至苏门答腊岛，长4000km。: "Permian strate of the Shan-Thai terrance in Thailand consist of the clastic sequence of the Kaeng Krachon Group and the conformably overlying carbonate sequence of the Ratburi Group ...[which] can be traced widely from Malaysia, through peninsular Thailand, Myanmar, West Yunnan, to Lhasa."
概述
西侧以实皆断裂与缅甸中央盆地相邻；东侧以一个较宽的印支期造山带与印支地块和东马来地块分开。

地块基底仅出露于滇西和缅甸，在滇西称为公养河群，在缅甸称为昌马支超群，为一套砂泥质变质岩系。公养河群被含化石的上寒武统整合覆盖，而昌马支超群则与上寒武统不整合覆盖。盖层从上寒武统一直延续到三叠系，基本上是连续沉积，其上有少量侏罗、白垩纪红层。盖层的石炭、二叠纪沉积中含有冰水沉积和冷水动物群化石，说明本地块原本是冈瓦纳大陆的一部分。晚古生代二叠纪末从东冈瓦纳分离出来，向北漂移，三叠纪末与印支地块碰撞: "Thailand consists of Shan–Thai and Indochina Microcontinents or Terranes welded together by the subsequently deformed Nan Suture.... During the Middle Triassic Shan–Thai sutured nearly simultaneously to Indochina and to South China, the continent–continent collision being a part of the Indosinian Orogeny and Indochina tended to underthrust Shan–Thai."，成为欧亚板块的一部分。

掸泰地块在古特提斯洋中是一个跨越几个维度的列岛。因而可以分为几部分，具有不同的古地理历史。"Thai" elements, bordering the Indochina block, are of 华夏古陆n type and characterised by palaeo-tropical warm-water 沉积相. The external "Shan" part has Gondwanan cold-water facies whilst the central "Sibumasu" part is transitional between the other two.
The internal parts of Shan–Thai merged with Laurasia  when the Nan-Uttaradit suture closed.
Oceanic basins separated the other elements of Shan–Thai until the Late Triassic–Early Jurassic Late Indochina Orogeny.

The collision between India and Eurasia during the Oligocene and Miocene resulted in clockwise rotation of south-west Asia, severe deformation of south-east Asia, and the extrusion of Shan–Thai and Indochina blocks.  These two blocks are still crisscrossed by the faults from this collision.

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Category:地质学
Category:亚洲地理