Did you ever wonder why the ocean is so much saltier than lakes?

By David McClelland

Well, I did and I did some research on this question. It seems that all water, even rain water, contains dissolved chemicals that scientists call salts. We drink fresh water and think it tastes good. Lake and river water contains some salt, but not much by comparison with ocean water. Ocean water it too salty for human consumption. Why? Because ocean water contains a much higher concentration of salts. The ocean is about 3½ % salt, by weight. In fact, if the salt from the ocean could be removed and spread evenly on the earth's surface, it would form a layer approximately 500 feet thick or about the height of a 40 story building. That is a lot of salt. No wonder ocean water tastes salty.

Where did all of that salt come from? Ocean water is a combination of mineral salts and of decayed biological matter that results from the teeming life in the seas. Most of the oceans salts were derived from gradual processes such as the breaking up of the cooled igneous rocks of the earth's crust by weathering and erosion, the wearing down of mountains, and the dissolving action of rains and streams which transported their mineral washings to the sea. Sodium Chloride constitutes 85% of the dissolved solids in the seas.

In summary, the ocean is salty because of the gradual combination of dissolved chemicals eroded from the earth's crust and washed into the sea in addition to the decaying of sea life.