Ocean Salinity reuptake

[neutrino_cannon]

While I do not readily aknowlege any ingnorance that may be lurking in my skull, I do here and now, so pay close attention, it may be a while before it happens again.

In the "silly creationist arguments" thread, Someone was kind enough to provide me with a link to talkorigins.org that showed (with an argument from a creationist, among others) that the salinity in the ocean is at a steady state, even though salt is being added by rivers.

My question is:

Did I miss something, or did they never mention the reuptake device? And if so, what is it?

I did a googling using something like ocean salinity reuptake, and the result is in the "woo woo water" thread (yeah, that's where it came from, the both of of those freakish monstrisities).

[Denise]

Why do you think salt is added by the rivers? It seems to me that the oceans bring salt into the rivers and that is why you have a brackish area. I am not highly educated on this, but this is my gut reaction to your post.

[neutrino_cannon]

Originally posted by Denise
Why do you think salt is added by the rivers? It seems to me that the oceans bring salt into the rivers and that is why you have a brackish area. I am not highly educated on this, but this is my gut reaction to your post.

I was just thinking of the great salt lake, my understanding of which was that rivers bring in small amounts of saline disolved material, and in a salt lake there is no place for it to go.

I could be wrong though (did he just admit to ignorance again? The implications are shattering!).

I see your point about brackish areas, but if the ocean has higher saline content, but is in equalibrium, I don't see the problem.

Except for my lack of understanding the reuptake mechanism.

[Soapy Sam]

One major way to get salt out of a lake or ocean is simply- evaporate the water. Leave the salt behind, put the water somewhere else.
Nature does this on a grand scale, evaporating whole ocean basins to form massive beds of salt. (Not all sodium chloride- various other salts in there too, mostly calcium and magnesium).

Laid down as an evaporite sequence, salts are then typically buried by other sediments. As sediment load builds up on top, the salt, being less dense, can actually rise up through the overlying rock, like the goo in a lava lamp. As it does so, it distorts the rock above and around it, fracturing rocks at the surface. (The rib structures in Arches National Park are formed by salt domes below.) Salt domes are major petroleum traps as well.

Eventually, the salt reaches an erosion surface, where groundwater leeches it into rivers and wash it back to the sea.

[Houngan]

What soapy said.

There are cycles for all of the important elements, namely C, P, N and the compounds like CO2, H2O, and O2. The short story is that minerals are washed out of the soil by erosion and rivers, flow into the sea, and become sediments. Along the way, there are many things (organisms) that grab what they can and keep the stuff in their ecosystem. Nitrogen in particular is exceedingly eroded due to man's influence on the ecosystem, and that is why your bag of fertilizer is mostly nitrogen, with some phosphorus and ammonia (more nitrogen) thrown in. It's also why lakes and oceans cycle phases over time, as particular mineral deposits are depleted, the users die off, the other users rise, the mineral concentration increases, the original users rise again. The minerals are (somewhat) returned to the system by oceanic upwelling, which allows access to the microbial users at the shallower depths. On the whole, though, we're depleting the store much faster than it is naturally replaced, so we're going to have some problems in the future unless we start transferring all the good stuff out of the reservoirs and back onto dry land, since we can't wait around for natural vulcanism to do the job for us.

H.