超级地幔树对全球构造的控制作用  

Control of super mantle trees over globe tectonics

作　　者：於文辉[1,2] 何发岐 袁茂山 王杰 刘德民 张世晖[1] 卞爱飞[1] 杨屿[5] 杨力行 YU Wehui;HE Faqi;YUAN Maoshan;WANG Jie;LIU Demin;ZHANG Shihui;BIAN Aifei;YANG Yu;YANG Lixing(China University of Geoscience(Wuhan),Wuhan,Hubei 430074,China;Terramagis Energy Technology Co.,Ltd.,Wuhan,Hubei 430074,China;SINOPEC North China Oil and Gas Com pany,Zhengzhou,Henan 450006,China;Hubei Earthquake Administration,Wuhan,Hubei 430071,China;Research Institute of Petroleum Erploration and Development,PetroChina,Beijing 100083,China)

机构地区：[1]中国地质大学(武汉),湖北武汉430074 [2]武汉拓盟能源科技有限公司,湖北武汉430074 [3]中国石油化工股份有限公司华北油气分公司,河南郑州450006 [4]湖北省地震局,湖北武汉430071 [5]中国石油天然气股份有限公司勘探开发研究院,北京100083

出　　处：《地质学报》2024年第3期653-661,共9页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号40774062,41641037)资助的成果。

摘　　要：全球横波低速异常体成像发现:Jason超级地幔柱与Tuzo超级地幔柱彷佛植根于地球外核顶部、生长在核幔边界(core-mantle boundary,CMB)上的两株榕树,我们将其命名为超级地幔树(super mantle tree),以突出Jason超级地幔柱与Tuzo超级地幔柱连接地核与地壳的纽带特征,强调它们在地球演化过程中对全球构造的作用。地幔柱仅是超级地幔树的局部分支。我们定义超级地幔树为4层结构:(1)植根于地球外核顶部;(2)1600~2890 km为“树干”;(3)110~1600 km为“树冠”;(4)110 km以上为“树枝”。“树枝”平面分布形态与全球板块轮廓大致相似,意味着板块构造可能起始于地球110 km处。推测地球深度1550~1600 km之间可能存在一个地球化学过渡层;Jason超级地幔树与Tuzo超级地幔树之间可能存在地球化学分隔面(简称地幔分隔面),地幔分隔面将地球划分为太平洋半球与大西洋半球;它的地面投影北端大致指向地磁北极,南端基本指向地磁南极。外核顶部脉动作用可能是地幔运动的动因,地核运动控制地幔运动。Tuzo超级地幔树逆时针旋转控制大西洋半球旋转形态,Tuzo超级地幔树的“细树干”伸向南大西洋,Tuzo超级地幔树“粗树干”伸向北大西洋,使得中大西洋脊减薄。Jason超级地幔树顺时针旋转控制太平洋半球旋转形态以及环太平洋地区地貌构造形态。青藏高原及邻区地质地球物理三维构造模型说明:向北运动的Tuzo超级地幔树“树枝”与向西运动的Jason超级地幔树“树枝”共同作用,形成青藏高原东构造结。Jason and Tuzo super mantle plumes together resemble a banyan tree growing on the core-mantle boundary(CMB) with a “root” on top of the Earth's outer core,“trunk”(1600~2890 km),“crown”(110~1600 km),and “branches”(above 110 km) and are thus termed “super mantle trees” to reflect the integrity of low-shear-wave-velocity anomalies in the mantle and highlight their role in the connect the core and crust and their effects of global tectonics during Earth's evolution.Here,we show that a mantle plume is a part or “branch” of a super mantle tree.The planar distribution resembles the global plate contour and basalt age distribution,i.e.,plate tectonics may start at 110 km.A geochemical transition layer may lie at 1550 km to 1600 km,with different geochemical indexes for the upper and lower spaces.There may be geochemical(mantle) separation surfaces between Jason and Tuzo super mantle trees,with the northern and southern ends approximately pointing to the geomagnetic north and south poles,respectively,and current growth spaces in the Pacific and Atlantic hemispheres.A three-dimensional(3D) structural model of the Tibetan Plateau and surroundings shows that the rotation of Jason and Tuzo super mantle trees changes or destroys the basic global tectonic framework,which the canopy movement further refines and transforms into a complex and regular panorama.

关 键 词：超级地幔树 全球构造 地幔分隔面 地幔运动 青藏高原三维构造模型 

分 类 号：P542.5[天文地球—构造地质学]