Field of Science

Accretionary Wedge #28: Have you ever danced with the devil in the pale moonlight?

"Tell me something, my friend. You ever dance with the devil in the pale moonlight?"
(Batman 1989)

Strange signs can be found in some rocks of the Dolomites, they resemble s
omehow the imprint of a hoof, but a very large hoof!

Ancient myths know for certain, that these must be the imprints of the hoofs of the devil and his demons.
Dark legends tell also about places where the devil meets witches and sorcerers, who sell their soul to him and gain magic powers and the ability to shift their shape.

Fig.1. Marcantonio Raimondi (1475-1534) "Lo stregozzo" ("The witches gathering", 1520-1527).

Some of these sorcerers like even to adopt the form of a putrefied mule skeleton during these gatherings.

Fig.2. David Ryckaert the Younger (1612-1661) "La ronde de Les Farfadets" ("The Dance of the Elves").

Dancing the entire night long they leave back only the imprints of their hoofs in the rocks, b
ut at the first cockcrow, even the mightiest evil force has to retire back into hell.

Modern explanation for the strange hoof-like cross sections is maybe less scarier, but not less intriguing:

The region of the Dolomites during the Norian-Rhaetian (216-199Ma) was situated in an extensive tropical shallow water zone. Gradually this area deepened again, but always remained still under a few meters to tens of meters of water column, while in the west and east deep basins developed due to tectonic processes. At the top of this giant submarine ridge limestones were deposited.
The Dachstein limestone is composed of well bedded limestones and reaches some hundreds of meters thickness. Like in the Hauptdolomite one can find several breccia layers composed of material swept together by storm events. Some of them show outstanding black mud pebbles, which are indicative for larger areas having been islands for a longer time.
The deeper parts were colonized by bivalves and single cora
l colonies. These bivalves (Megalodus in the Hauptdolomite and Conchodon in the Dachstein limestone) can often be observed in cross sections and inspired various myths in the Dolomites to explain them.

Fig.5. Bedded Dachsteinkalk- Formation, the cross sections are quit hard to recover, however...

Fig.6. a hand-specimen that made it until home - of Megalodus gümbeli from the Hauptdolomit-Formation. During the recrystallization of the limestone the calcite components of the shell got lost, here we see an interior cast of the bivalve (makes it also easy to release it from its rock - grave)


VOLKMAR, S. & VOLKMAR, M. (2005): Introduction to the geology of South Tyrol. Ufficio geologia e prove materiali - Provincia Autonoma di Bolzano-Alto Adige: 80

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