大陆褶皱造山运动的星地碰撞成因

Continental Folding Orogenesis from the Perspective of Collision Dynamics of a Celestial Body with the Earth

大陆褶皱造山运动具有突发性、全球同步性,以水平运动为主,主要表现在地壳上部且具有上强下弱等特征,除水平运动一项外,与基于地幔对流的板块构造理论缺少共同之处.想用板块构造理论解释遍布大陆地块内部的褶皱构造,在形位特征与动力机制上都有难以解决的矛盾.基于地球自转速度变化的地质力学理论,对之所做的定性解释颇为合理,但因其只靠地球收缩及潮汐引力等缓变力作为引起地球自转速度变化的动力来源,力量强度太小,不足以引发强大的褶皱造山运动,且有被海水运动取代的难题.揭示了星地碰撞可以为大陆造山运动提供足够强大的突发性动力来源,并简要阐明了其作用机制,可以解决地质力学所遇到的力源不足和被海水运动取代的两大难题,从而为大陆构造研究开辟了一个新境界.

The continental orogenesis is characterized with the following features, such as sudden start, global synchronicity and horizontal movement, occurring mainly in the upper part of the crust and weakening with depth, and so on. It is difficult to explain these characteristics by the plate tectonic theory based on the heat convection in earth mantle. The geomechanics based on the change of rotating speed of the earth could answer a large part of the above mentioned questions, but the power which it depends on offered by the expansion or contract of the earth and tides et al is too weak to serve as the energy to change the rotating speed of the earth, so it is also difficult to explain them quantitatively. This paper reveals the collision energy of a celestial body with the earth could induce a sufficient change of rotating speed of the earth to make the folding orogenesis, and briefly explains its mechanics, and therefore offers a brandnew perspective for researching continental orogenesis.