U/Th dating of freshwater travertine from Middle Velino Valley (Central Italy): paleoclimatic and geological implications M. Soligo a , P. Tuccimei b; Ã , R. Barberi c , M.C. Delitala b , E. Miccadei d , A. Taddeucci b a Dottorato di Ricerca in Geodinamica, Universita ' ‘Roma Tre’, L.go S. Leonardo Murialdo 1, 00146 Rome, Italy b Dipartimento di Scienze Geologiche, ‘Universita ' Roma Tre’, L.go S. Leonardo Murialdo 1, 00146 Rome, Italy c Rilevatore CARG, Rome, Italy d Dipartimento di Scienze della Terra, Universita ' degli Studi ‘G. d’Annunzio’ di Chieti, Via dei Vestini 31, 66013 Chieti Scalo (CH), Italy Received 18 May 2001; accepted 14 February 2002 Abstract Six travertine bodies outcropping along the Middle Velino Valley (Central Italy) have been studied and dated using the U/Th method in order to obtain new chronological constraints for the recent geological evolution of the area. The lithological and sedimentological characteristics of travertines have been described, showing that such deposits can be referred to waterfall, pool terraces and gentle slopes environment. Travertines have formed during warm periods and can be referred to marine oxygen isotope stages 5, 3 and 1. Travertine deposition seems to stop around 5 ka BP according to other European and Italian sites. Pollen stratigraphy and ostracod assemblages from the close sequence of Valle di Castiglione, characterized by the same climatic conditions of Velino Valley, have confirmed that periods of Velino Valley travertine deposition were effectively characterized by warm and wet climatic conditions. Seismic activity strongly active in the area since the Middle Pleistocene has deeply influenced the location and the discharge of springs which have deposited the travertines, influencing in turn the shape and size of travertine bodies. ß 2002 Elsevier Science B.V. All rights reserved. Keywords: U/Th dating; travertine; Velino Valley; Central Italy; warm periods; seismic activity 1. Introduction Recently travertine deposits have been consid- ered as indicators of warm climatic phases in the continental environment (Pentecost, 1995; Frank et al., 2000; Horvatincic et al., 2000). Increased frequencies of travertine growth have been found in various European sites during interglacial peri- ods (Pentecost, 1995; Maire, 1990), as already known about speleothems (Gascoyne et al., 1983; Maire, 1990). In order to verify such ¢nd- ings, travertines from the Middle Velino Valley (Central Italy) have been studied and dated using 0031-0182 / 02 / $ ^ see front matter ß 2002 Elsevier Science B.V. All rights reserved. PII:S0031-0182(02)00253-5 * Corresponding author. Tel.: +39-06-54888092/70; Fax: +39-06-54888201. E-mail address: tuccimei@uniroma3.it (P. Tuccimei). Palaeogeography, Palaeoclimatology, Palaeoecology 184 (2002) 147^161 www.elsevier.com/locate/palaeo