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Re: definitions



At 04:11 PM 8/9/97 -0400, you 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

(Or, more broadly: lacustrine, adj., "of the lake").

>   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

Lagerstatt (singluar), lagersta:tten (plural, umlaut over the second "a"):
any sedimentary unit with spectacular accumulations of fossils.
Lagerstatten are divided into Konzentrat-lagerstatten (where fossils are
preserved at very high numbers, such as Cleveland-Lloyd or your typical
shell-hash coccina) or Preservat-lagerstatten (where the fossils are
spectacularly preserved).  Preservat-lagerstaten can be any sort of
sedimentary rock type, and some include lithographic limestones (Solnhofen,
Las Hoyas), anoxic shales (Burgess Shale, Holzmaden, Hunsru:ck), units with
silicified fossils, etc., etc.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661