基于洋板块理论对内蒙古古生代地层区划分的实践和认识  

PRACTICE AND UNDERSTANDING OF PALEOZOIC STRATIGRAPHIC REGIONALIZATION IN INNER MONGOLIA BASED ON OCEANIC PLATE THEORY

作　　者：张玉清[1] 张建 许立权[1] 康小龙[1] 王忠[1] 张永清[1] 王弢[1] 罗忠泽[1] 李文国 ZHANG Yu-qing;ZHANG Jian;XU Li-quan;KANG Xiao-long;WANG Zhong;ZHANG Yong-qing;WANG Tao;LUO Zhong-ze;LI Wen-guo(Inner Mongolia Key Laboratory of Magmatic Mineralization and Ore-Prospecting,Geological Survey of Inner Mongolia,Huhhot 010020;No.8 Institute of Geology and Mineral Exploration and Development,Wuhai 016000;Inner Mongolia Institute of Geology and Resources Mineral Exploration,Huhhot 010010)

机构地区：[1]内蒙古自治区地质调查院,内蒙古自治区岩浆活动成矿与找矿重点实验室,内蒙古呼和浩特010020 [2]内蒙古第八地质矿产勘查开发院,内蒙古乌海市016000 [3]内蒙古地质矿产勘查院,内蒙古呼和浩特010010

出　　处：《地层学杂志》2020年第1期82-94,共13页Journal of Stratigraphy

基　　金：中国地质调查局项目(12120113013200)资助。

摘　　要：内蒙古较为系统的地层划分始于1978年,之后在编写内蒙古自治区区域地质志、内蒙古第二代区域地层表、内蒙古自治区岩石地层以及内蒙古矿产资源潜力评价成矿地质背景等论著时,均对内蒙古全区古生代岩石地层进行了详细的划分与研究,采用的理论体系为"槽台论"和"板块构造"。本次地层区划将新理论--大洋板块地层系统(Ocean Plate Stratigraphy,OPS)引入其中,与以往不同之处是分别建立了大陆板块地层系统和大洋板块地层系统。大陆板块地层包括陆块区及大陆边缘两大部分的沉积产物,大洋板块地层是大洋板块消减过程中形成的无序岩石组合,野外露头上表现为"俯冲增生杂岩"。据此,内蒙古古生代岩石地层划分为五个一级地层大区,以古亚洲洋消减对接带为限,东北部属西伯利亚地层大区、西北部为塔里木地层大区、南部归华北地层大区,该对接带本身称为恩格尔乌苏-西拉木伦(古亚洲洋消减对接带)地层大区,秦祁昆地层大区位于华北地层大区之南,以龙首山断裂为界。根据古地理环境、岩石组合及古生物化石等因素的差异,进一步将其划分为8个地层区、13个地层分区,其中鄂尔多斯地层分区细划为4个地层小区。一级地层区划(地层大区)的边界与板块构造的边界基本一致。该地层区划或将对中国北方大地构造的认识起到积极的推动作用。The systematic stratigraphic classification of Inner Mongolia began in 1978, and subsequently the Paleozoic lithostratigraphy in Inner Mongolia were divided and studied in detail by compiling the regional geology of Inner Mongolia Autonomous Region. The theoretical systems of "the geosyncline-platform theory" and "plate tectonics" were adopted for the second-version of the "Regional Stratigraphic Chart of Inner Mongolia", "Lithostratigraphy of Inner Mongolia" and in the evaluation of metallogenesis and geological background of Inner Mongolia for mineral resources potential, etc. Present paper adopts the new theoretical system(Oceanic Plate Stratigraphy, OPS), i.e. the continental plate stratigraphic system and the oceanic plate stratigraphic system, for the stratigraphic division of Inner Mongolia. Continental plate stratigraphy in the area involves two major sedimentary types: continental block area and continental margin. Oceanic plate stratigraphy deals with the disordered rock assemblages formed during the subduction of an oceanic plate. As a result, the Paleozoic stratigraphy of Inner Mongolia is divided into five stratomegaregions. Bounded by the Ancient Asia Subduction Zone, the northeastern part of Inner Mongolia belongs to Siberia stratomegaregion, northwestern part is referred to Tarim stratomegaregion, and southern part to the North China stratomegaregion. The subduction zone of the Paleoasian Ocean itself is termed Engel Usou-Xar Moron stratomegaregion. The Qin-Qi-Kun stratomegaregion is situated to the south of the North China stratomegaregion, bounded by the Longshoushan Fault. The boundaries of the primary stratigraphic divisions(stratomegaregion) are basically coincident with those of plate tectonics. According to the paleogeography, paleoclimatic features, rock assemblage, paleobiological fossils and other characteristics of stratomegaregions, five stratomegaregions are further subdivided into 8 stratoregions, and 13 stratosubregions. In addition, the Ordos stratosubregion is subdivided into 4 st

关 键 词：地层区划 大洋板块地层 古生代 内蒙古 

分 类 号：P534.4[天文地球—古生物学与地层学]