- 志仁Lv 61 十年前最愛解答
The sea water was fresh water in the first place. While after the ice age, there are lots of rains. The rains fell on the land and wash away the minerals on it. Many of these minerals are in form of salts (salts mean many kinds of salt), that why there are salts in thsea today. You can imagine that even nowadays, the rain still washing the minerals on land to the sea, so the sea is more salty.