摘要
洋中脊是大洋的胚胎,从洋中脊为地堑式中央裂谷的形态特征来看,大洋是拉张应力的产物,因此必须依据大陆漂移造成海底被动扩张这一结论来分析研究板块运动的动力源问题。大陆漂移的方向是有规律的,根据世界大洋年龄图等资料进行逆推,还原不同阶段的洋陆展布状态,可以看出,白垩纪以来南半球大陆分解向北运动、北半球大陆分解向南运动,大陆在向低纬度地区运动的过程中向西运动,这种大陆漂移的方向性特征与地球自转力作用的方向性特征完全吻合。根据模拟实验,在空心不锈钢球体的中高纬度表面吸附具有一定质量的磁扣并旋转不锈钢球体,当达到一定转速时,磁扣会向赤道漂移,同时向西漂移。同理,地球上的大陆高出大洋,当中高纬度的大陆自转离极力大于前方大洋阻力时,必然会造成大陆在大洋之上仰冲,也就是大陆在大洋之上漂移。根据离极力理论计算可知,中心在中纬度的大陆产生的离极力足以使前方大洋破裂屈服,从而发生指向赤道方向的逆冲运动;而向赤道运动的大陆因旋转半径变大会产生强烈的向西的同步力,造成大陆西侧大洋破裂并发生逆冲运动,从而向西漂移。板块运动的本质就是大陆挤压大洋造成洋壳破裂逆冲,陆壳于洋壳之上作仰冲运动,大陆前方的古大洋逐渐被俯冲消亡,最终与前方大陆碰撞造山合并成新的大陆;而由于大陆的前行造成其后的岩石圈普遍处于张裂状态,导致原大陆被拉张分解为2个或多个陆块,分裂的陆块之间沿洋中脊增长生长为新大洋。地球自转形成的地转力除造成板块运动外,还可能使岩石圈内部发生断裂,并在已有断裂上积累和释放势能,从而造成地震。
The mid-ocean ridge is the area where the ocean crust grows.It is a central rift,reflecting that the ocean is a product of tensile stress.Therefore,we must study and analyze the power source of plate movement based on the conclusion that the continental drift causes passive expansion of the ocean floor.The direction of the continental drift is regular.Inversion is performed according to the world ocean map and other data to restore the ocean and continent distribution positions at different stages.It can be seen that since the Cretaceous,the continental decomposition of the southern hemisphere has moved northward,and the continental decomposition of the northern hemisphere has moved southward.The continent moved westward as it moved towards the equator.This directional characteristic of continental drift exactly matches the directional characteristic of the Earth’s rotation force.According to the simulation experiment:the magnetic buckle with a certain quality is attracted to the middle and high latitudes of the surface of the hollow stainless-steel sphere,and the sphere is rotated.When the rotation reaches a certain speed,the magnetic buckle drifts toward the equator and westward.Similarly,because the continent on the earth is higher than the ocean,when the Earth’s rotation departure pole force of the middle and high latitudes is greater than the resistance of the ocean crust ahead,it inevitably causes the continental thrust and drift above the ocean.The theoretical calculation of Earth’s rotation departure pole force,which is generated by a continent centered at mid-latitudes,is sufficient to rupture and yield the ocean in front,so that the continental thrust drifts towards the equator.The continent moving toward the equator causes a strong westward synchronizing force due to the change in the radius of rotation,causing the ocean on the west side of the continent to rupture and the continent to drift westward.The essence of plate movement is that the continent squeezes the ocean,causing the crust of the ocean to rupture and subduct.The old ocean in front of the continent is gradually subducted and destroyed.Eventually,the continent collides with the front continent to form a new continent.Becausethe earth is a whole,the rocks behind the continent circle is under tension stress.The original continent is stretched and decomposed into two or more continents.The split continents grow along the mid-ocean ridge and grow into a new ocean.The Earth’s rotation departure pole force,formed by the rotation of the earth,in addition to causing plate motion,may also cause fractures within the lithosphere,and the accumulation and release of potential energy on existing faults may cause earthquakes.
作者
方曙
FANG Shu(Inner Mongolia Autonomous Region Tenth Institute of Geological and Mineral Exploration and Development,East-Wangfu Street,Chifeng 024005,China)
出处
《大地测量与地球动力学》
CSCD
北大核心
2021年第6期551-560,共10页
Journal of Geodesy and Geodynamics
关键词
板块运动规律
海底拉伸扩张
地转力实验
地转离极力
地转同步力
the law of plate movement
stretched seafloor expansion
Earth rotation force experiment
Earth’s rotation departure pole force
Earth rotation synchronization force