Re: Miller on Submarine Vents

> From: "Perplexed in Peoria" <jimmenegay@xxxxxxxxxxxxx>
> My point (and Miller's, I believe) is that the temperatures deep in
> the vents are high enough to drive the system to chemical
> equilibrium, so there won't be any complex organics in the vent fluid.

Yes, however the fact that today there's a rich community of organisms
feeding off such vents must show you that you somehow have overlooked
something? Here's what it is: The very very hot fluid which came
through the hottest part of the vent may be in chemical equilibrium,
but that's not the same equilibrium that the cold seawater surrounding
the vent is at, and where one glides past the other, at the boundary
between those two regions of equilibrium, where diffusion carries
material back and forth, the situation is not at all near equilibrium.
Complex chemical cascades could very well occur in that narrow boundary
region. Any complex chemicals that result from those cascades would
either be drawn back into the vent, where they'd be decomposed again,
or left in the relatively sargasso region in the center of the
convection cell where they could last indefinitely. New catalysts could
be randomly created there, half of which would be destroyed and half of
which would be safe for a while, and OOL could occur there per my
catalytic chain scenerio.

> However, Wachtershauser makes the point that when the temperature of
> the fluid is quenched by contact with the ocean, the fluid will still
> be simple, but it may now be far from equilibrium. Just the situation
> needed for an autotrophic origin.

Yes, but moreso an abiotic chemical cascade set too, possibly forming
non-simple food-chemicals in sufficient quantity that a
semi-autotrophic replicator could survive, not just an
ultra-autotrophic replicator. (Sorry I can't remember the terminology
you invented months ago, but you get the idea what I mean? Not just
C(1)-consuming replicators, but probably also C(2)-consuming
replicators and maybe even C(3+)-consuming replicators for small to
medium values of 3+.

> The "hot" side of a convection cell is just not hot enough to break
> down organic chemicals (ie. their covalent bonds).

Yes, that's why I mentionned Tom's solar-cycle relocted to a
vent-convection-cell-cycle as a possible driving force to some sort of
forced cyclic reaction that replicates something. That makes my
J.Random catalytic chain closure scenerio more likely, where part of
the chain is enhanced by warming and another part of the chain is
enhanced by cooling. (And when a huge comet/asteroid crash causes a
ten-year-long "nuclear winter", killing Tom's solar-cycle critters, my
convection-cell critters survive nicely.) (Also Tom's solar-cycle is
something like 10-15 hours long (back when the Earth spun faster),
which is still too slow for many chemical reactions, whereas convection
cells have a wide range of cycle times from seconds to hours so
somewhere there may have been one that cycled at a suitable rate to
drive a reaction-cycle effectively.)

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