< p >有趣的问题。< / p > < p >只要板块构造持续下去,那么,作为@Arkenstein提到,造山运动和海洋盆地的形成将创造足够的地形多样,确保土地的存在。此外,只要有一个大陆和海洋岩石圈之间的区别,我们将大洲。< / p > < p >但这不会永远持续下去。在某些时候,板块构造将停止地球内部的热量生产下降。在这一点上,假设其他什么也没发生,我们会逐渐看到山脉侵蚀,与海填满——略——与沉积物。侵蚀停在海平面,误差,但海平面本身变化随着时间的推移,你可能期望一个很浅的世界海洋的大陆。< / p > < p >,但不是唯一。< / p > < p >如果板块构造停止,我们可能会搬到一个Mars-style政权,与热点热传输的主要方式。与火星,我们将看到巨大的盾牌火山形式,基本上像冰岛。 So imagine an ocean planet with some massive circular islands dotted about, as the old continents eroded down. Of course, this won't actually happen; within about a billion years, the sun will get so hot that a runaway greenhouse effect will come into operation, and the oceans will evaporate, ending pretty much all life on earth, and the possibility of a global ocean. Indeed, with no mountains to draw down CO2 by erosion, a water world may be very unstable as regards runaway greenhouse effects.