attribution to the early Galerian, and probably to the Colle. Curti Faunal Unit (~ 1.05 Ma), whose type locality is located just few km East from the Umbria-Marche ...
Rend. Online Soc. Geol. It., Vol. 21 (2012), pp. 1075-1077, 1 fig. © Società Geologica Italiana, Roma 2012
Multidisciplinary study of a new Quaternary mammal-bearing site from Ellera di Corciano (central Umbria, Italy): preliminary data MARCO CHERIN (*), ROBERTO BIZZARRI (*), NICOLETTA BURATTI (*), TIZIANA CAPONI (**), FRANCESCO GROSSI (°), TASSOS KOTSAKIS (°), LUCA PANDOLFI (°), FAUSTO PAZZAGLIA (*), MASSIMILIANO R. BARCHI (*)
grain size analysis and determination of Atterberg’s limits, and the evaluation of CaCO3 percentage with the Dietrich-Frühling calcimeter, was carried out along the section, aimed to a comprehensive characterization of the main clay horizons. Measured values highlight the main lithological changes (alternation between clays and calcareous tufa); furthermore, minimal variation among fossiliferous clay levels are also recorded, indicating minor transitions between different depositional systems (flood deposits, distal alluvial fan deposits, etc.). Excavations for paleontological purposes were carried out till August, 2011 and allowed to recover more than 200 vertebrate specimens, mainly referred to large mammals. Recovery methods were partially borrowed from archeological field methods: each specimen was numbered and photographed, and its absolute position and height was registered with a GPS instrument, in order to place them on a digital map. The realization of a 3D model of the area, with the topographic position of each sample together with some anatomical and taphonomic characteristics (type of bone, presence/absence of articulation, fragmentation, etc.), is currently in progress. Bone samples were discovered within three different clay levels in a span of ~ 3 m (height of the lowest specimen: 246.2 m; height of the highest specimen: 249.4 m above sea level). In the lower mammal-bearing level, called “hippo level”, a partial skeleton of Hippopotamus cf. H. antiquus was found, together with other isolated and fragmented bones. Most of the collection (more than 100 samples) was recovered from the intermediate level; the state of preservation was good on the whole, even if almost all the bones were fragmented, suggesting a certain degree of water transport. In the upper level, a partial skeleton of Mammuthus sp. was discovered; it is composed by both the tusks, some vertebrae, and an almost complete posterior leg. Just below the “mammoth level”, some very bad preserved bones were collected from a single clay level showing an advanced state of pedogenesis; bones were all fragmented, white-colored, and their surface was cracked with a “mosaic” pattern, suggesting a longer exposition to subaerial conditions. Beyond the above-mentioned Hippopotamus cf. H. antiquus and Mammuthus sp., the other recognized taxa are: Panthera cf. P. gombaszoegensis, Axis eurygonos,
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Key words: calcareous tufa, geotechnics, intermontane basin, fossil mammals, ostracods, palynology, sedimentology.
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A new fossil mammal-bearing site was discovered at Ellera di Corciano (PG) on April, 2011 in a building site where a large mall is under construction. The first bones were recovered by one of the Authors (T.C.), during a survey for archeological purposes. Excavations were funded and directed by the Soprintendenza per i Beni Archeologici dell’Umbria, with the scientific and technical support of the Department of Earth Sciences, University of Perugia. The presence of fossil mammals in the Ellera area has been already reported by PETRONIO et alii (2002) and ARGENTI (2004), who cited a small association recovered from the “exLancia De Poi” site and referable to the upper Villafranchian; this fauna is currently in course of revision because it has been found within the same clay levels that outcrop in the site described in the present work, just few hundred meters SE. The Ellera area is part of a sedimentary basin whose genesis started in the Early Pleistocene, with a progressive isolation from the easternmost, larger Tiber basin. The evolution of the Ellera basin was controlled by synsedimentary tectonics, in extensional regime. The stratigraphic section (more than 16 m thick) in the mammal-bearing site is the following: - 0.00-3.15 m: calcareous tufa (phytoherm, phytoclastic, micrite) with cavities filled by red clays; - 3.15-7.62 m: clay and silty clay with two thin levels (10 cm) of phytoclastic tufa. Clays show a strong pedogenesis (root traces, CaCO3 nodules), contain pulmonate molluscs and are rich of organic matter, especially in the upper part; - 7.62-16.30 m: prevalent phytoclastic and phytoherm tufa alternating with clay and silty or sandy clays. Siliciclastic levels present evidences of pedogenesis, while tufa levels host cavities filled by red clays. A sedimentological and geotechnical survey, including _________________________ (*) Dipartimento di Scienze della Terra, Università degli Studi di Perugia (**) Dipartimento di Scienze dell’Antichità, Sapienza Università di Roma (°) Dipartimento di Scienze Geologiche, Università degli Studi Roma Tre
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18-20 SETTEMBRE 2012, ARCAVACATA DI RENDE (CS)
Fig. 1 – Partial skeleton of Mammuthus sp. before its recovery. In the background, the building activities was in progress. Length of the white folding rule: 2 m.
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Praemegaceros cf. P. verticornis, Bison degiulii, and Equus sp. Scanty remains of small vertebrates are preliminarly referred to Emydidae, Soricidae and Arvicolidae indet. Some coprolites have also been found. Praemegaceros cf. P. verticornis is represented by three basal portions of antler, belonging to an adult and two juvenile individuals. They show strong affinities with the antlers of P. verticornis from Ponte Galeria, that is considered a primitive form of this species, referred to the subspecies P. verticornis dendrocerus by AMBROSETTI (1967), and to the forerunner species P. pliotarandoides by CROITOR & KOSTOPOULOS (2004). The large deer remains from Ellera noticeably differ both from P. obscurus from Pietrafitta and Eucladoceros spp. from different Italian sites. Bovid remains are quite abundant and represented by cranial and post-cranial elements. All the remains lack the typical characters of the Villafranchian genus Leptobos, while they show high similarities with B. degiulii from Pirro Nord and Capena. From a biochronological point of view, the occurrence of Praemegaceros cf. P. verticornis and B. degiulii suggests an attribution to the early Galerian, and probably to the Colle Curti Faunal Unit (~ 1.05 Ma), whose type locality is located just few km East from the Umbria-Marche boundary. Both micropaleontological and palynological analyses are
currently in progress in order to depict the paleoenvironmental conditions. Preliminary micropaleontological results show that the lower sample (“hippo level”) yielded few ostracod valves referable to Cyprideis sp. instars, and the same very scanty and monospecific assemblage with Cyprideis sp. instars has been recognized also in the intermediate sample, testifying for both samples a very shallow oligohaline waterbody. The upper sample (“mammoth level”) yielded an abrupt change in the ostracod assemblage: biodiversity and frequency increased, with Ilyocypris gibba and Candona sp. juv. as dominant species, accompanied by Potamocypris sp., Pseudocandona sp. and Heterocypris sp. (fragments), testifying a shallow and freshwater permanent waterbody more suitable to host benthic association. At the state of the art, the integration of sedimentological and micropaleontological data allows to infer two principal depositional environments: a periodically flooded alluvial plain, with ponds and mires (deposition of clays, silty and sandy clays, paleosols) and a lacustrine/palustrine environment (deposition of calcareous tufa). REFERENCES AMBROSETTI P. (1967) - Cromerian fauna of the Rome area. Quaternaria, 9, 1-17.
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137-159. PETRONIO C., ARGENTI P., CALOI C., ESU D., GIROTTI O. & SARDELLA R. (2002) - Updating Villafranchian molluscs and mammal faunas in Umbria and Latium (Central Italy). Geol. Romana, 36, 369-387.
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ARGENTI P. (2004) - Plio-Quaternary mammal fossiliferous sites of Umbria (central Italy). Geol. Romana, 37: 67-78. CROITOR R. & KOSTOPOULOS D.S. (2004) - On the systematic position of the large-sized deer from Apollonia, Early Pleistocene, Greece. Paläontologische Zeitschrift, 78 (1),
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