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Solnhofen Taphonomy

>Actually the short answer is "not very much" :-)
>Saline water is denser than freshwater (due to the amount of salts disolved
>in it), and hypersaline water is denser than normal sea water. Therefore
>the freshwater entering the lagoon will tend to stay separate from, and
>flow over the much denser hypersaline water (cue horrible ascii diagram).
>    *          Freshwater/Normal Saline   **
>      *----------------------------------*   *
>        *       Hypersaline             *      *
>           *  *  *  *  *  *  *  *  *  *          *
>Thus the benthic (bottom) conditions remain hypersaline despite freshwater

Chris -

        Thanks for the refresher course!  8-)  Of course, since the waters
won't mix, that presents problems for the excellent preservation of the
fossils -- dead animals (of the terrestrial variety, washed in from
wherever) will float a while before sinking to the anoxic, hypersaline
bottom waters for preservation, and during that floating would undergo some
decomposition.  We do see that in some of the _Archaeopteryx_ specimens,
and some of the other vertebrates, but we also get the truly gorgeous ones
that appear to have been buried the instant they died!  I doubt that the
influx of stream waters was anoxic.  Hmmmm....a puzzle!  8-)  Is there a
solution you can propose?  I'm at a loss (but then again, I'm no expert in
taphonomy, either...)

Jerry D. Harris
Schuler Museum of Paleontology
Southern Methodist University
        (Compuserve:  73132,3372)

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"South American Animals and Their Lice"

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