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塔里木盆地中部有一条近东西向的重磁高异常带,火成岩露头仅见于西部的巴楚地区。采集25件晋宁期火山岩样品进行研究,地球化学特征表明岩石形成的大地构造背景为洋岛,且可清楚地区分出洋岛碱性玄武岩(亚速尔型洋岛)和洋岛拉斑玄武岩(夏威夷型洋岛),两者反映了洋盆发育的不同阶段。一件晋宁期超基性岩样品显示出岛弧岩浆岩的性质,与塔里木中部地区的闪长岩和花岗闪长岩应同为晋宁期岛弧的记录。它们可能指示一条横贯塔里木盆地中部的晋宁期古缝合线,原称的塔里木板块(克拉通)是由两个原先分隔的地块在晋宁运动时碰撞拼合而形成的,并成为罗迪尼亚超大陆的一部分。该古缝合线在震旦纪—中生代构造活动性较强,尤其是二叠纪—三叠纪的构造—岩浆事件规模较大。据此讨论了晋宁期构造—岩浆活动在认识基底形成、区域演化和油气勘探中的意义。
There is a nearly east-west high gravity-magnetic anomalous zone in the central Tarim Basin. The igneous rock outcrops are only found in the Bachu area in the west. A total of 25 samples of the Jinning Period volcanic rocks were collected and studied. The geochemical characteristics indicate that the geotectonic background of the rocks is the Oceanic island, and the distinction between Yangdao alkaline basalts (Azores) and Ocean Island tholeiites (Hawaii Type oceanic island), both of which reflect the different stages of oceanic basin development. A Jinning ultrabasic rock sample shows the properties of island arc magmatic rocks, and should be recorded in the same period as the Jinning Period Island arc with the diorites and granodiorites in the central Tarim. They may indicate an ancient Jinning period suture that traverses the central part of the Tarim Basin. Formerly known as the Tarim Plate (cratonic) was formed by the collision and combination of two previously separate plots during the Jinning movement and became Rodini Part of the sub-continent. The ancient suture in the Sinian - Mesozoic tectonic activity is strong, especially in the Permian - Triassic tectono - magmatic events on a larger scale. The significance of the Jinning period tectono-magmatism in recognizing the formation of basement, regional evolution and oil and gas exploration is discussed.