弧形构造带形成演化特征研究  

Formation and evolution characteristics of arcuate tectonic belt

作　　者：马海勇[1] 罗安湘[2] 王朝阳[1] 欧阳征健 冯娟萍[1] MA Haiyong;LUO Anxiang;WANG Chaoyang;OUYANG Zhengjian;FENG Juanping(College of Geology and Environment,Xi’an University of Science and Technology,Xi’an 710054,China;Research Institute of Petroleum Exploration and Development,Changqing Oilfield Company,Xi’an 710018,China;Bailie School of Petroleum Engineering,Lanzhou City University,Lanzhou 730070,China)

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]长庆油田分公司勘探开发研究院,陕西西安710018 [3]兰州城市学院培黎石油工程学院,甘肃兰州730070

出　　处：《西安科技大学学报》2022年第4期752-759,共8页Journal of Xi’an University of Science and Technology

基　　金：国家自然科学基金项目(41502107);陕西省自然科学研究计划项目(2018JM4033)。

摘　　要：为研究弧形构造带形成演化特征,以六盘山弧形构造带早古生代晚期形成的弧形构造为例,采用野外面地质调查、数值模拟等研究手段,对弧形构造带形成规律进行区域块体应力定量化的数值模拟分析。结果表明:六盘山弧形构造带受到青藏地块向北东向的推挤,北祁连地块也向北东向位移并推挤北祁连弧后盆地,北祁连弧后盆地被相对坚硬的阿拉善地块与鄂尔多斯地块阻挡。早古生代晚期六盘山区域北东向挤压的构造应力是早期弧形构造形成的主要原因,利用数值模拟方法构建的古生代晚期的数值模型,进行构造应力与地质块体形变规律数值模拟计算,使地质模型处于平衡状态后获得x方向、y方向位移,在x方向的位移,计算结果显示六盘山区域范围内古生代地质块体向东最大位移约为向北最大位移的25%,位移向量的位移方向总体表现为向北东弧形突起的构造形态。研究结果可为区域弧形构造演化研究提供定量化分析的参考和理论依据。In order to study the formation and evolution characteristics of arcuate tectonic belt, the arcuate structure formed in the Late Early Paleozoic in liupanshan arcuate tectonic belt as an example.By means of field profile geological survey and numerical simulation, an analysis was made of the formation rule of regional block stress in the initial stage of arc tectonic belt formation.The results show that the tectonic belt was pushed NE by the Qinghai-Tibet block, and the North Qilian blocks also moved NE and pushed the North Qilian back-arc basin, which was blocked by the relatively hard Alxa block and Ordos block.The tectonic stress action of the NE compression in the study area in the late Early Paleozoic is the main reason for the formation of the early arc-shaped structure.The numerical model of the tectonic belt in the late Paleozoic was constructed via the numerical simulation method to examine the tectonic stress and the deformation law of the geological block.After numerical simulation, the model was in equilibrium with the displacement in x direction and y direction obtained.The displacement calculation results in x direction show that the maximum eastward displacement of the Paleozoic geological block in Liupanshan region is about 25% of the maximum northward displacement, and the displacement direction of the displacement vector is generally presented as the structural shape of arc-shaped protrusion in northeast direction.The results can provide a theoretical guidance for quantitative analysis of regional arc tectonic evolution.

关 键 词：弧形构造 六盘山 构造演化 数值模拟 位移向量 

分 类 号：TD121[矿业工程—矿山地质测量]