摘要:板块构造理论可以被认为是构造地质学研究的基本模型和框架。传统板块构造理论认为岩石圈板块在软流圈上方随软流圈对流发生运动，软流圈对流所需要的能量则完全由地球内部能量，如重力势能和放射性衰变产生的热能提供。但是近年来的一些研究证明了气候变化会对板块构造活动，如造山带活动产生直接影响。对传统的板块构造所需能量全部由地球内部提供这一观点做出了补充和更新。本文主要从两个方面对外动力作用可能影响板块构造做出分析，一是利用傅里叶分析证明了太阳辐射变化在构造活动，如洋中脊两侧地貌和火山沉积物中均能够留下记录；二是建立了一个简单的平面力学模型，探究洋流同大陆的力学作用会如何影响大陆运动特征。虽然这一模型忽略了很多因素，定量计算的结果本身并不具有很严格的数据绝对意义。但是这一模型的结果可以证明地球所有板块构造活动中释放的能量低于地球系统每年从太阳辐射中接收的能量，而且模型得到的大陆运动特征同现今实际观测下的运动特征存在一致性，洋流向大陆岩石圈传递的能量同地震活动释放的能量处于同一量级，从侧面可以证明洋流可能对板块构造产生了较大的影响。?
关键词: 板块构造/
太阳辐射/
傅里叶分析
Abstract:The theory of plate tectonics could be seemed as the basic framework for studies on geological structures. The traditional plate tectonics theory suggests that Earth’s lithosphere is broken up into plates and moves above the underlying asthenosphere. Density variations and energy from the decay of radioactive elements drive convections in asthenosphere. However, some recent studies showed that climate changes could directly affect tectonic activities such as orogeny. Furthermore, some studies have found that the variation of solar insolation was recorded in some records of tectonic events. These research suggests that variations of solar insolation could have a first-order effect on plate tectonics, which may make people rethink about the idea that endogeneous energy provide all the energy that plate tectonics need. We analyzed how solar insolation could affect plate tectonics from two aspects. First, we used Fourier analysis to prove that the variations of solar insolation were recorded in tectonic records, like seafloor bathymetry and volcanic sedimentary rocks. Second, we built a simple 2-D mechanical model to analyze whether oceanic currents could affect plates’movements. Although many factors were neglected in calculations, the results could be meaningless. But from these calculations we could prove that solar insolation could provide more energy than those which is released by tectonic events. Also, some results from the model calculations are accord with current plate movements, and the energy transferred to plates are in the same amount with that which was released by earthquakes. This may suggest that ocean currents could potentially affect plate tectonics.?
Key words:Plate tectonics/
Solar insolation/
Fourier analysis
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