The paleogeography of Italy has always been the subject of debate due to the geological complexity of the Italian peninsula and its islands, but also due to the past scarcity of fossil material relating to Mesozoic vertebrates. Today, however, the growing discoveries of fossils, in particular of dinosaur traces and remains, are rewriting Italian paleogeography.
But first of all, what is Paleogeography and what does it deal with?
Paleogeography is a branch of geology and, more generally, natural sciences, which deals with reconstructing the geographical position of the earth over the course of geological time, and to do this it makes use of contributions from numerous disciplines, such as biostratigraphy, Absolute Chronology, Sedimentology, Basin Analysis, etc.
Until 2005, the classic vision of Italian paleogeography from the Mesozoic onwards was that of an area between Laurasia and Gondwana characterized by low sea environments (Tethys) with separate islets. However, the growing discovery of remains, especially of fossilized traces of dinosaurs, has changed everything. In fact, these discoveries supported the hypothesis that several times during the geological time the Italian area was composed of emerged lands and that in some moments these were also in continental connection. The findings of dinosaur remains have therefore led to the conclusion that there were adequate conditions for the presence of diversified associations of dinosaurs and that therefore, there was the availability of freshwater, food, and potentially suitable places for nesting. This implies the presence of lands that emerged not only as islands but in continuity with each other.
The geological evidence shows how up to the Upper Cretaceous the Panormide Platform (“Sicilian” equivalent of the Apennine Platform in the Apennines) determined a continental continuity with the Apennine platform and the Apulian platform, also determining a continuity with Africa and separated the Ionian Tethys from the Ligurian Tethys (also called the Ligurian Ocean). Subsequently, however, an extensive phase lasting from the upper Cretaceous to the Eocene (from 100 million years to 33 million years ago) not only dismembered the platforms, determining the emergence of some areas and the submersion of others but also determined the dismemberment of the Panormide Platform.
The remains and fossil traces of dinosaurs found in the Palermo area testify to this past continuity
(Panormide), the discovery of the Scypionix “Ciro” (Apennica), the footprints of Altamura (Apula).
In particular, the traces found in the Palermo area concern theropod bones found at Pizzo Muletta within the chain of the Palermo Mountains. This find makes this a key area in what used to be the continental bridge between Africa and Adria. The detailed geological and sedimentological studies of the Pizzo Muletta succession have identified the theropod bones falling into section M, relating to environments proximal to those of the beach.
Furthermore, the Pizzo Muletta area and the paleontological discoveries indicate that this was a crucial point in the migration patterns of dinosaurs. In short, few finds, but of extraordinary interest and very high value!
Randazzo, Vincenzo & Di Stefano, Pietro & Schlagintweit, Felix & Todaro, Simona & Cacciatore, Maria & Zarcone, Giuseppe. (2021). The migration path of Gondwanian dinosaurs toward Adria: New insights from the Cretaceous of NW Sicily (Italy). Cretaceous Research. 126. 104919. 10.1016/j.cretres.2021.104919.
Zarcone, G., Petti, F., Cillari, A., DI STEFANO, P., Guzzetta, D., & Nicosia, U. (2010). A possible bridge between Adria and Africa: New palaeobiogeographic and stratigraphic constraints on the Mesozoic palaeogeography of the Central Mediterranean area. EARTH-SCIENCE REVIEWS, 103(3-4), 154-162 [10.1016/j.earscirev.2010.09.005].