Cherves-de-Cognac

["David Marjanovic" <david.marjanovic@gmx.at>]

Eh, les mecs ! Voyons si j'peux encore bavarder en anglais... eeeeuh...
errr... yo guys, lessee if I can still speak English. :-)

>From July 1st to 19th, I was at a dig in the gypsum quarry of
Cherves-de-Cognac in southwestern France (near Cognac, where the distillate
comes from, and which is near Angoulême which is "near" Bordeaux), situated
between vineyards. It was organized by the university of Poitiers (Prof.
Jean-Michel Mazin, famous since Crayssac) and will continue until July 30th
(almost nobody stays for the whole month, but there are always something
like 20 to 25 people there). The largely marly sediments are Berriasian in
age, like much of Purbeck -- and unlike any other not fully marine site I
know of. They represent a receding sea; at the base there are evaporites
(the gypsum), higher up there are lagoonal-estuarine sediments and even at
least one small river channel.

There are thousands of fish scales (*Lepidotes* -- which means that the
scales are made of enamel and usually well preserved). There are also bones
of *Lepidotes*; I found several ?operculars (gill-covering bones; horribly
fragile), many fragile ribs, and a jaw or palate (also very fragile) with
many tiny spherical teeth. Next most common are fragments of turtle armor (a
common smooth and a rare somewhat spiny species), followed by fragments of
croc osteoderms, coprolites that now remind me of JP4, and croc teeth. There
are probably 4 species of croc...odyliform :-) in that quarry: a pholidosaur
(gavial-like) -- on our 1st day in the field we found a 1/2-m-long complete
skull with a disarticulated lower jaw --, 2 species of goniopholidid (their
sometimes 5 cm long robust teeth had carinae for cutting) and an atoposaurid
(a lovely dwarf croc, represented this year only by tiny osteoderms). Small
head and fin spines of hybodontiform "sharks" (*Polyacrodus*) can also be
found. Several big croc vertebrae turned up, too. Last but not least we
found 2 teeth of a big theropod, 1 tooth of a small theropod (strongly
recurved, serrations on the distal carina but no carina at all at the mesial
side) and a fragment of a camarasaurid tooth.

Screenwashing produces charophytes, ostracods, "shark" teeth, snails and
eggshell fragments.

There are no pebbles in the sediment. If you find something, you know it is
either one of the very rare concretions of manganese/iron oxide or a fossil.
(Or a recent root.)

The dig has a website (unfinished) at http://cherves.chez.tiscali.fr (no
typo, 3 dots). You'll also find last year's dig there, which yielded, as I
was told, a gigantic coprolite (had to be plastered, naturally!) , teeth
from all sorts of dinosaurs including a "bird" (apparently an
archaeopterygid), and 2 mammal teeth, at least one of which is from a
peramurid. As Purbeck is famous for its mammal fauna, expect more.

Last week I was on a totally different dig organized by the university of
Vienna (and I have to return on Monday for a few more days). I need a
certain amount of hours of excavations, so I chose this didactic dig in the
Miocene (pretty precisely 15 Ma ago) seafloor (Paratethys) in a ?wheat field
close to the Czech border. Not interesting (strongly disturbed alternations
of clay and storm sediments that consist of sand and shells), but still more
so than the eternal cave bears... from which I can't escape, in September
they'll catch me.

(Sorry that I ignored the girls in the first line... that's for dramatic
effect, as contemporary French, AFAIK like English, hasn't invented a new
word for them. :-] )