Here's a question: ancient ocean salinity levels?

[Sk8r]

facts: 1) ocean level fluctuates massively with ice ages and meltdowns; and ice is freshwater. The salt stays in the non-frozen water.
2) extinct coral colonies found miles inland in Florida, many feet down continental shelf in Australia, so corals were 'traveling' in the generational sense, establishing wherever they could.
3) corals reseed shallows, build new reefs; the Great Barrier Reef is about 12,000 years old, from the Big Melt at the end of the last major ice age. There have been minor events (the Little Ice Age) less affecting sea levels.
4) chemicals like salt don't evaporate, no matter how much the seas rise or fall due to melt.

So....how tolerant can coral species be of gradual salinity/calcium/mg change, how extreme can it get without extinction, and how did coral species manage to survive with all this going on for millions of years?

Is anybody doing work on the chemistry of ancient oceans? Any articles, etc?

 

[ruprecht]

During the Holocene (<10kya) sea levels dropped (glaciation). I have seen the effects when diving barrier reefs, there's a huge notch in the reef, much like the bioerosion you see in Palau limestone islands, but at like.... can't remember 60 feet maybe? Temperature was up, salinity was up. Here's some numbers. Corals are tough. The environmental changes that those surrounding high islands go through are quite incredible. Rain, tides, flat hot summers. I've seen colonies high and dry baking in the sun and seen them bathed in sediment laden freshwater runoff. Healthy as can be to this day. Short term is one thing obviously, millenia another. Coral are weeds though they can grow anywhere and they will be here long after we are gone.

 

[Sk8r]

Thank you! Interesting article!