地球科学工作者将地球的形状看成是“地球体”,即由海平面和大陆上地表水体及潜水面所共同环抱构成的球体。地球固体表面的总垂直起伏约为20公里,实际地表形态要复杂得多。人们无法直接观察地球内部,多半通过地震方法间接推测。本世纪三十年代,K.E.布伦经过计算,将地球内部划分为三个同心圈层,由表及里依次是地壳、地幔和地核。此后,通常将地壳和上地幔的最顶部合称为岩石圈。岩石圈的底面 Earth science workers regard the shape of the earth as a “globe,” a sphere of oceans that is surrounded by sea level and the surface and submersible surfaces of the continent. The total vertical fluctuation of the Earth’s solid surface is about 20 km, which is much more complicated in terms of surface morphology. People can not directly observe the interior of the earth, mostly indirectly estimated by seismic methods. In the thirties of this century, K.E. Burren calculated to divide the interior of the earth into three concentric circles, followed by the crust, the mantle and the earth core. Since then, the top of the crust and upper mantle has generally been collectively referred to as the lithosphere. The bottom of the lithosphere