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Re: extinction



----- Original Message -----
From: "Simonyi" <huibm012@attglobal.net>
To: <dinosaur@usc.edu>
Sent: Sunday, January 11, 2004 9:44 AM
Subject: extinction

>  The very fine powder form (so called Ir-soot) can produce IrO2 at
> atmospheric pressure and medium high temperature but it isn't found in the
> nature. The common form of Ir can oxidize in pure oxigen atmosphere and
> high temperature and pressure only.

But we are not talking about Ir-soot, not about atmospheric pressure, and
not about medium high temperature. We are talking about an explosion several
orders of magnitude BIGGER than if ALL the world's nuclear weapons at the
height of the Cold War would have exploded on the same spot. Depending on
how you measure, the Chicxulub crater is up to 300 km in diameter.

Thus, we are talking about a fireball, about plasma with one Ir atom in
every, whatever, cubic meter. Certainly some Ir oxides and chlorides will
precipitate out of this plasma when it cools down.

> The so called hydrogen-chloro-iridiumate can produce from
> sodium-chloro-iridiumate what can produce from Ir and NaCl in chlor
> atmosphere at high temperature. This combination isn't in the nature.

But in the fireball that results from a _gigantic_ impact into a shallow
sea.

> And where is potassium nitrate in the atmosphere?

Why in the atmosphere? Nitrate is everywhere else, in seawater, in soils...
*Escherichia coli* in your gut breathes nitrate if it has no more oxygen.

> 3. ACCORDING THE TIME OF IRIDIUM ANOMALY
>
> 3.1. Mr McLean wrote:
> 'New information on this topic can be found in a paper by Zhao et al.
> titled "A possible causal relationship between extinction of
> dinosaurs and K/T iridium enrichment in the Nanxiong Basin, South
> China: evidence from dinosaur eggshells" (Palaeogeography,
> Palaeoclimatology, Palaeoecology, 2002, v. 178, pp. 1-17).
>
> The authors indicate that iridium and other trace element buildup in
> the environment, and consequently in dinosaur tissues, likely caused
> pathological thicknesses in dinosaur eggs, and microstructural
> alterations of the eggshells. Because multiple iridium spikes were
> distributed over a temporally long Cretaceous-Tertiary duration, they
> indicate also that the source of the iridium was likely the Deccan
> Traps volcanism, and not an asteroid impact.'
>
> 3.2. My reaction:
> The large impact didn't leave time for dinosaurs
> to produce these pathological eggs.
>
> According my theory it was enough time to cause this problem.

However, we _have_ the big impact, so we _must expect_ a catastrophic mass
extinction. The impact was there, we cannot ignore it.
        Abnormally thick eggshells occur at any time in any place, and are
not concentrated at the K-T boundary; most importantly, they can result from
all sorts of stress, by no means only from Ir!

> I wrote about "fossils" not only "fossils of dinosaurs" therefore Mr
> Bigelow didn't answer to my question.

OK, then take the acid rain as an explanation. :-)
More important is that the fossils of coccolithophorids and forams _form_
rocks that consist of little else than of the fossils. A cemetery of those
would not look different from any other part of _chalk_ or _sandstone_,
respectively.

> Again, this is generally a problem with fossil frequencies across the
board.
> There must have been more babies dying than adults at all times, not just
> during the K/T event, yet juveniles are rather rare.  There are various
> reasons for this, some are in the archives.'
>
> 5.2. My answer:
> I wrote about so special "cemetery" where can find in same place many of
> young individuals, old ones, healthy ones, sick ones, etc.

Dinosaur fossils are comparatively rare. Cemeteries of that sort (called
bonebeds) more or less exist, but fewer than 10 (I think) are known for the
entire Mesozoic. The impact should have related in the sudden death of lots
of dinosaurs, but their fossils would, if at all, not all be found in the
same place!