About 71% of the surface of the earth is covered by ocean. That leaves about 29% in the continents. So there is roughly 2.5 times as much ocean as continent.
It has many features for more information type this in:How are the features the same or different?
That it is a topgraphical and the features are a ocean floor.
Earth's crust is composed of the continents and the ocean floor.
The oldest rocks on the continents would be much older than the rocks on the sea floor because the rocks on the continents are not being removed unlike the rocks on the sea floor that are made by the mid-ocean ridge are being removed by deep ocean trenches. this prossess that is occuring on the sea floor is called sea floor spreading. evidence of this is the Pacific ocean shrinking and the Atlantic ocean growing.
Ocean topography is very similar to that on land. The different conditions do result in unique features, however.
The crust contains the ocean floor and also the continents on Earth.
Is a diverse as that of the continents
Tectonic Plates can't carry both ocean floor and continents on the same plate.
What causes ocean floor features to form
The continents and the ocean floor rest upon the plates.
The same size as all the continents combined
Plate tectonics and (river) erosion are responsible for the formation of ocean-floor features.