地球内部过程 Plate Tectonics The Topography of the Sea Floor: If South america and africa really have moved apart one might expect to see some evidence of this between them some feature or features on the sea floor to indicate the continents passage. A topographic map of the floor of the Atlantic Ocean shows an obvious ridge running north-south about ha lfway不彻底 中途 between those continents大陆间近南 北向的明显洋脊. This mid- ocean ridge might be the seams from which the two continents moved apart. Similar ridges are found on the floors of other oceans as seen in the same figure. In other places, frequently along the margins of continents, there are trenches沟堑 several kilometers deep. It remained for scientists studying the ages and magnetic properties of seafloor rocks as described below, to demonstrate the significance of the ocean ridges to plate tectonics. The trenches, too, can be explained by plate tectonics 环境迪顶学 minoucntalocelogu地球内部过程 • Plate Tectonics The Topography of the Sea Floor： If South America and Africa really have moved apart, one might expect to see some evidence of this between them, some feature or features on the sea floor to indicate the continents’ passage. A topographic map of the floor of the Atlantic Ocean shows an obvious ridge running north-south about halfway不彻底、 中途 between those continents大陆间近南 北向的明显洋脊. This mid-ocean ridge might be the seam缝 from which the two continents moved apart. Similar ridges are found on the floors of other oceans, as seen in the same figure. In other places, frequently along the margins of continents, there are trenches沟堑 several kilometers deep . It remained for scientists studying the ages and magnetic properties of seafloor rocks, as described below, to demonstrate the significance of the ocean ridges to plate tectonics. The trenches, too, can be explained by plate tectonics