HORNUNG, T. (2002)
Eine Fossilbank in der Riffschuttfazies des Untersten Unterkimmeridge Ludwags (Oberfranken)
A fossil layer in the
reef-detritus facies of the basalmost Kimmeridgian of Northern Franconia
The area around the village
Ludwag is famous for its well-preserved ammonite faunule within shallow basinal
and reefal facies. In the framework of a paleontologic-palecologic diploma thesis
several localities in the lower Ludwag quarry were studied in detail, both in
the well bedded, marly shallow basinal facies ("Bay of Ludwag", see
BRACHERT 1986) and in the biostromal reef detritus facies embracing the Oxfordian-Kimmeridgian
boundary. In both facies subzones two distinct condensed ammonite layers occurred.
Inspite of the closeness of both subfacies zones, the layers were not to correlate.
Differences in preservation - the biostromal facies provided bodily preserved
specimen, the basinal facies planar deformed specimens - could be explained
with variable content of calcium carbonate.
The basal ammonite layer with a average thickness of 20 cm was unearthed planar in cooperation with the Museum of Natural History, Bamberg and the Institute of Paleontology, Erlangen in May 2001.
BRACHERT, T. (1986): Eine Mikrofaziesanalyse im Neuen Steinbruch Ludwa / Ofr. (Unteres Unterkimmeridge) mit Betrachtungen zur Morphologie von Biohermen (Oberes Oxford). - unveröffent. Dipl. Arb., 125 S, Erlangen.
|published in: Geol. Bl. NO-Bayern 52, 1-4: 69-84, Erlangen|