提肯乃克特额尔齐斯构造混杂岩带的初步确立及构造意义

提肯乃克特额尔齐斯构造混杂带岩块(片)由变质玄武岩及变质辉绿岩、斜长花岗岩等深成杂岩组成,可能代表了北准噶尔有限洋盆的洋壳残片,基质主要为一套浅变质细碎屑岩,上覆岩石主要由硅质岩、变质粉砂岩等远洋沉积物组成。早泥盆世,准噶尔微板块东北缘及西伯利亚板块南缘因大陆硅铝壳开始破裂、扩张,在额尔齐斯断裂南北两侧分别出现拉张活动。中泥盆世,哈萨克斯坦-准噶尔板块向山区阿尔泰地块俯冲并逐渐闭合成陆。早石炭世初期,准噶尔微型板块北缘再次沿额尔齐斯断裂带南侧发生拉张、裂陷,逐渐演变成活动大陆边缘并发育基性杂岩体。早石炭世晚期,地壳由扩张转为挤压,准噶尔微板块与阿尔泰地块再次发生碰撞,伴随这次板块碰撞活动,其上覆上迭火山-沉积盆地闭合成陆。提肯乃克特额尔齐斯构造混杂岩带的识别,对于重新认识准噶尔地块和阿尔泰地块之间的关系及探讨中亚造山带古生代以来的构造演化具较大意义。

Preliminary Establishment and Tectonic Significance of Tekennakte Erzis Tectonic Melange Belt

The rock assemblages of the Tekennakte Erzis Tectonic Melange belt are composed of fereomagnesian vol- canic rocks dominated by metamorphic basalts and metamorphic diabase and plagioclase granite,It may represent the remnants of the oceanic crust of the limited oceanic basin in North Junggar.The matrix is mainly composed of a set of shallow metamorphic fine clastic rocks.The rocks covered on it are mainly composed of pelagic sediments such as sili- ceous rocks and metamorphic siltstones.In the Early Devonian,the northeastern Junggar micro-plate and the southern Si- berian plate,because of the continental silica-aluminium began to disintegrate and expand,and tensional activities oc- curred on both sides of the Erzis fault.During the Middle Devonian,the Kazakhstan-Junggar plate subducted to the Altay massif in the mountains area and closed gradually to form land.In the early Middle Carboniferous,the Junggar micro- plate once again strethched and collapsed along the southern side of the Erzis fault zone,gradually evolving into active continental margin and developing basic complex. In the late Middle Carboniferous,the crust changed from expansion to compression , and collision activity occurred again between the Junggar micro-plate and the Altay block.Accompained by this collision movement, the superimposed volcanic sedimentary basins on it area closed into continents.The identifi- cation of Tekennakte Erzis Tectonic Melange belt,it shows a great significance for re-recognizing the relationship be- tween the Junggar and Altay blocks and discussing the tectonic evolution of the Central Asian orogenic belt since the Pa- leozoic.