中国西北地区沉积盆地发育的区域构造格局与演化  

Regional tectonic framework and evolution of superimposed basins in northwestern China

作　　者：何治亮[1] 高山林[1] 郑孟林[2] 

机构地区：[1]中国石化石油勘探开发研究院,北京100083 [2]中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000

出　　处：《地学前缘》2015年第3期227-240,共14页Earth Science Frontiers

基　　金：国家重大专项(2011ZX05005-002)

摘　　要：中国西北地区是不同地质时期多个全球性大地构造单元的组成部分,具有南北分带、东西分区的构造特征,经历了中、新元古代—古生代期间地壳增生、洋-陆转换、板块开-合旋回、晚二叠世以来盆地的叠加改造和新生代印度与欧亚板块碰撞远源效应等长期演化过程,具有明显的阶段性。研究表明,现今盆地多位于具有一定规模的经过前震旦系不断增生作用所形成的陆块基底之上,塔里木盆地塔中、塔北、塔东北地区基底可能以古元古界为主,而巴楚地区则以晋宁期的变质基底为主。准噶尔盆地前震旦纪存在多个独立发育的块体,古生代总体具有多岛洋的性质。柴达木盆地、河西走廊及邻区的诸多中小型盆地的基底主要为中元古代形成。敦煌盆地、北山地区众多中小型盆地坐落在中小地块或者古生代活动陆缘的岛弧之上。西北地区早古生代经历了一个完整的板块开-合旋回,但不同地区有不同表现方式。北疆地区至少存在寒武纪—早奥陶世、志留纪和泥盆纪3个主要时期的蛇绿岩,反映了在早、晚古生代各存在一定规模的洋盆。在不同带的早古生代洋盆具有不同的闭合时间。塔里木盆地周缘南天山洋、西昆仑洋及阿尔金、祁连、东昆仑、北山地区早古生代洋盆的发育时间为寒武纪早期,经过了中、晚寒武世到早奥陶世早期洋盆的扩张,早奥陶世晚期构造应力场转为挤压体制。志留纪中晚期至早泥盆世,西北地区存在全区性的板块拼合与碰撞以及不同程度的变形变质过程。西北地区晚古生代又经历了一个完整的板块开-合旋回,天山全区、准噶尔南部、东西两侧分别进入碰撞后新的大规模的伸展阶段,均形成了有限洋盆,其时代略有差别,上、下石炭统之间可能存在构造转换。塔西南地区早石炭世伸展作用形成了晚古生代的西昆仑洋和陆缘裂陷盆地,中二�The northwestern China is a component of several global tectonic units in different geological periods, with the structural characteristics of N-S zoning and E-W districting. This area underwent crustal growth, ocean-continent transition, and oceanic basin open and close cycles in the Middle Neoproterozoic to the Paleozoic. The evolution process has obvious periodic characteristics, with superimposing and rebuilding since the Late Permian and with the far source effect of India and Eurasia plate collision in the Cenozoic. Most basins are based on the variable sized Pre-Sinian crystalline basements; the basements of Tazhong, Tabei, and Tadong areas may be of the Proterozoic, whereas basement of Bachu region was Jinning period metamorphic rocks; The Junggar Basin based upon different sized independently developed pre-Sinian basements displayed the tectonic pattern of archipelagic ocean during the Paleozoic. Many small-medium size basins in the Hexi Corridor, the Qaidam Basin and adjacent areas were developed on small blocks or Paleozoic active continental margin arcs with crystallized Proterozoic basements, and different metamorphic events took place and formed bolded basement under the Dunhuang Basin. The northwestern China underwent a full plate open close cycle in the early Paleozoic, accompanied with diversified presentation in different regions. The ophiolites occurred more than three times in the northern Xinjiang region in the Cambrian - Early Ordovician, the Silurian and the Devonian, respectively, which were identified as certain scale oceanic basins in the Paleozoic with different closing periods in disparate area. The South Tianshan ocean around Tarim Basin and oceanic basins developed around West Kunlun, Ark/n, Qilian, East Kunlun, and Beishan underwent oceanic basin expansion from the Middle and Late Cambrian to the Early Ordovician, with the tectonic setting transition from the compressional system to the tensional system in the late period of the Early Ordovician. In the Late Siluri

关 键 词：中国西北地区 区域构造格局 构造演化 盆地基底 板块开-合旋回 复合叠加盆地 

分 类 号：P618.130.2[天文地球—矿床学]