By Anupum Pant
Until very recently, till the year 1979, we humans had no real explanation as to why the oceans were actually salty. If a kid ever asked that to the teacher, the teacher just tried go to the next question.
It was hypothesized that the rivers got in a lot of salts into the ocean and made them salty. However, that was a flimsy argument given the size of all the rivers and the cumulative size of all the oceans.
Later in the year 1979, while researchers were doing their job at around the East pacific rise (a divergent tectonic plate boundary located along the floor of the Pacific Ocean), the were greeted by mysterious vents in the ridge that were spewing big black columns of material into the ocean. These black dust like thing was later found to be a massive amounts of tiny crystals being thrown into the oceans by these hydrothermal vents.
It was found that the whole volume of water in all the oceans across the world cycled in and out of the earth through vents, into the tens of thousands of magma chambers, every 6-8 million years and carries enough chemicals back to the surface for these millions of years.