What is the origin of the ocean's salt?

Question

We know we cannot live without salt, but an investigation into the origins of ocean's salt leads one to believe that this issue is not fully resolved yet. What geological phenomenon caused the earth to contain so much of salt? I see questions on SE that ask about the origin of earth's water. In a similar vein did an extraterrestrial body "dump" salt on earth or is salt native to Earth? It appears from these links that Jupiter's Moon Europa does contain a salty ocean - http://www.space.com/20078-jupiter-moon-europa-ocean-surface.html and http://www.planetary.brown.edu/pdfs/2440.pdf. From a geochronology perspective what causes a planet to "develop" salt concentrations ?

Answer 1

The ocean’s salt did not come from one single event. It accumulated gradually as water interacted with rocks over geologic time.

Rainwater contains dissolved carbon dioxide and is slightly acidic. As it moves through soils and rocks, it chemically weathers minerals and releases dissolved ions. Rivers then carry ions such as sodium, calcium, magnesium, chloride, and sulfate to the ocean. Volcanic gases, submarine hydrothermal systems, and reactions between seawater and oceanic crust also contribute dissolved material.

Salt becomes concentrated because the water cycle removes mostly pure water by evaporation, while most dissolved ions remain behind. However, the ocean does not simply become saltier forever. Ions are also removed by processes such as mineral precipitation, biological activity, alteration of the seafloor, and burial in sediments. Ocean salinity therefore reflects a long-term balance between sources and sinks.

From a geologic-time perspective, the important issue is not a planet’s age alone but whether it has liquid water, reactive rock, and enough time for water-rock interaction and concentration. An enclosed ocean beneath the ice of Europa could become salty through reactions between water and its rocky interior even without rivers or an atmosphere like Earth’s.