Formation of the earth, oceans and continents (apply the big bang theory, continents drift theory, the plate tectonics theory, condensation of water ovapor, or other acceptable theory
after earth cooled down from being a large ball of molten lava , the water vapour in gaseous state turned into liquid and it poured rain for thousands of years filling all the oceans we see now and as the rocks were filled with salts and minerals the ocean became salty
