My friend, professor Steve Katz, and I took a walk along the shore of a nearby river to investigate.
Katz is an environmental scientist here at Washington State University. He pointed out some big rocks along the river. That’s where the salt comes from, he explained. Yep, it all starts with rocks and dirt.
Read all of this answer from Dr. Universe at https://askdruniverse.wsu.edu/2016/04/18/oceans-why-are-they-salty/.
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