Just offhand thought is the earths geology over time tends to remove salt from the ocean. An example is the Messinian Salinity Crisis when the Mediterranean sea

Just offhand thought is the earths geology over time tends to remove salt from the ocean. An example is the Messinian Salinity Crisis when the Mediterranean sea closed off and then mostly evaporated. The result was a huge layer of salt deposited under the seabed. And the rest of the earths oceans became much less salty. Would not surprise me if plate subduction doesn't sequester salts as well. https://www2.atmos.umd.edu/~dankd/MessinianWeb/_private/HOME.htm https://www2.atmos.umd.edu/~dankd/MessinianWeb/_private/HOME...