The ocean floor, like the surface of the land, is made up of many geological features. There are deep trenches that drop off from underwater plains. There are plateaus, ridges, and mountains that rise thousands of feet. Also, as on land, underwater surface features are formed or changed by the movements of tectonic plates and the action of water.
The huge bodies of salt water that we call oceans cover approximately three-fourths of the earth's surface. The Atlantic Ocean covers 33,420,000 square miles at an average depth of 11,700 feet. The Pacific Ocean covers 64,200,000 square miles at an average depth of 12,900 feet. The Arctic Ocean covers 5,120,000 square miles at an average depth of 3,400 feet. The Indian Ocean covers 28,400,000 square miles at an average depth of 12,600 feet.
If these oceans cover approximately three-fourths of the earth's surface, what is the total surface area of the earth? (Please round your answer to the nearest whole square mile.)