地球内部过程 Plate Movements-Accumulating Evidence 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. 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 seamsit 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 a r 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 ,率地球内部过程 • Plate Movements-Accumulating Evidence 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