Re: definitions

[Jonathon Woolf <jwoolf@erinet.com>]

Jeff Poling wrote:
> 
>    Are these definitions correct?
> 
>    lacustrine, adjective, describes a sedimintary deposit laid down by a
> lake.  Lacustrine deposits are often comprised of limestone, such as the
> Solnhofen and Liaoning lacustrine deposits

Yes, lacustrine deposits are lake-bottom deposits.  But they aren't
always limestone.  I think you can also have lacustrine shale.  

>    lagerstatten, adjective, describes a sedimentary deposit comprised of
> sediment of exceptionally fine grains.  Lagerstatten deposits often preserve
> the fine detail of fossils found within, such as the feathers of
> <I>Archaeopteryx</I> fossils from Solnhofen

This doesn't match my understanding of this word.  The word
_lagerstatte_ (plural, _lagerstatten_) is a German compound noun. 
According to Stephen Jay Gould, it translates literally to English as
"lode place."  It's used to describe any deposit that contains large
numbers (a motherlode) of superbly preserved _softbody_ fossils.  The
Burgess Shale is a lagerstatte; so is the Solnhofen Limestone; so is the
Mazon Creek deposit near Chicago.  I think you could call the Green
River Formation a lagerstatte too.  

-- JSW