"Thanks Pim, I had intended to mention this paper since it
is one of my main references in support of the idea that the
deep hydrothermal vents work against the notion that the
earth's early oceans contained a primordial soup. Previously
you asked me to define what I meant by this, I'll save that
for a another post."
I am still confused about this primordial soup ? What is your definition
of such ? Whatever the composition might have been, the existance of a
'primordial soup'
is almost self evident.
Here's a quote from the Miller&Bada paper:
< In summary, we have shown that the proposal for a hydrothermal
< vent origin of life fails each of the three proposed steps in
< the origin of life. Any origin-of-life theory that proposes
< conditions of temperature and time inconsistent with the
< stability of the compounds involved can be dismissed solely
< on this basis, unless some protective mechanism exists, but
< no such mechanisms are known at present. This is not to say
< that the hydrothermal vents were a negligible factor on the
< primitive Earth. They would have had a function in the elemental
< balance of the oceans as they do today. The vents would have
< been important in the destruction rather than in the synthesis
< of organic compounds in the primitive oceans, because the entire
< ocean currently passes through the vents in 10^7 years. In fact,
< this latter process was an important factor in fixing the upper
< limit for the organic compound concentration in the oceans of
< the primitive Earth.
< -- Miller and Bada, 1988.
"Two other outspoken critics of the hydrothermal vent scenario
are Gerald Joyce and E.G. Nisbet:"
Miller and Bada speak out against life originating at these locations but
they do suggest that hydrothermal vents could have been important for the
chemical mix required.
"To the scenarios which do not seem to require a primordial soup
in the oceans we need to add Nisbet's preferred scenario, a shallow,
luke-warm subaerial (land) hydrothermal system:"
This still requires a primordial soup. I am still confused about your
definition of such ? Even if the primordial soup was less concentrated and
evaporation was needed to increase the concentrations or if the soup was
located to distinct localities, a primordial soup still existed.
Thanks for the references. I am presently looking at a paper in which the
authors look at the generation of HCN and other chemicals in the
shockwaves of meteorites hitting out early earth.