Why is the ocean salty? Why is salt there?
Scientific theories behind the origins of sea salt started with Sir Edmond Halley in 1715, who proposed that salt and other minerals were carried into the sea by rivers after rainfall washed it out of the ground. Upon reaching the ocean, these salts concentrated as the process of evaporation removed the water. Halley noted that most lakes that don’t have ocean outlets (such as the Dead Sea and the Caspian Sea,), have high salt content. Halley termed this process “continental weathering”. Halley’s theory is partly correct. In addition, sodium leached out of the ocean floor when the ocean formed. The presence of salts other dominant ion, chloride, results from out-gassing of chloride (as hydrochloric acid) with other gases from Earth’s interior via volcanoes and hydrothermal vents. The sodium and chloride ions subsequently became the most abundant constituents of sea salt. Ocean salinity has been stable for billions of years, most likely as a consequence of a chemical/tectonic system whi
