地壳运动的原动力

Abstract

本文从地球形成和地球演化的角度出发，以地球体变的思路和物质运动的规律来分析地壳运动，提出地壳运动的原动力有四种，张力、挤压力、重力和形变力。张力来自于地幔的体积增加，地幔体积增加的因素是地球内部固体物质态变；挤压力来自于地幔的体积减少，地幔体积减少的因素是地球内部液态物质排放，物质排放的形式有洋壳顶置、火山喷发、岩浆侵入、排气和热液渗透等；重力来自于地壳质量的改变，改变地壳质量的因素是剥蚀、沉积、褶皱、断裂、火山堆积、底侵和俯冲等；形变力来自于地壳温度的改变，改变地壳温度的主要因素是底侵。物质态变导致地幔体积增加，物质排放导致地幔体积减少，简称地球体变。地球体变产生的张力和挤压力，是推动地壳运动的主要动力。地壳质量和地壳温度的改变，产生的重力和形变力，是推动地壳运动的次要动力。地壳运动原动力的研究，其意义在于用正确的思路解释各种地质构造。张力主要产生洋壳扩张现象；挤压力产生洋壳俯冲、转换断层、板块漂移、陆壳褶皱、剪切断裂和逆掩断裂等构造现象；重力是决定地壳上升或下降的因素；形变力产生弧后盆地、岛弧、陆壳张性断裂和陆壳折返等构造现象。 From the viewpoint of the earth formation and the evolution of the earth, this paper analyzes the movement of the earth’s crust, and puts forward four kinds of the original power, tension, pressure, gravity and deformation force. The tension comes from the volume increase of mantle. The factor increasing the volume of mantle is the state change of solid materials in the earth; the extrusion force comes from the reduced volume of the mantle. The factor reducing the volume of the mantle is the emission of the earth’s interior liquid substances. The form of substance emission includes oceanic crust overhead, volcanic eruption, magma intrusion, air exhaust, hot liquid penetration, etc.; the gravity comes from the change of the earth’s crust. The factors changing the mass of the earth’s crust and floating state include denudation, deposition, fold, fault, volcanic deposit, underplating, subduction, etc. The deformation force is derived from the change of the temperature of the earth’s crust. The main factor that changes the temperature of the crust is the bottom. The state change of substances leads to the increased volume of the mantle, and the emission of substances leads to the reduced volume materials, which is hereinafter referred to as the volume change of the earth. The tension and extrusion force produced by the volume change of the earth is the main power of the crustal movement. The gravity and deformation force produced by the change of mass and temperature of the earth’s crust is the secondary power of crustal movement. The significance of the study of the dynamic of the crustal movement is to explain the various geological structures in the correct way. The tension mainly produces the expansion of oceanic crust; the extrusion force produces subduction of oceanic crust, transform fault, plate drift, fold of continental crust, shear fault, overthrust fault and other structural phenomenon; the gravity is the factor which determines the crust rise or fall; the deformation force produces back-arc basin, island arc, extensional fault of continental crust, exhumation of continental crust and other structural phenomenon.