SESS 0_retro e indice edi.pub Il Quaternario Italian Journal of Quaternary Sciences 24, (Abstract AIQUA, Roma 02/2011), Congresso AIQUA Il Quaternario Italiano: conoscenze e prospettive Roma 24 e 25 febbraio 2011 INTEGRATING ARCHEOLOGICAL AND GEOMORPHOLOGICAL DATA TO EVALUATE THE LATE HOLOCENE EVOLUTION OF THE KARTALINI BASIN (GEORGIA) Stefano Furlani1, Alberto Stinghen2, Luca Bertoldi2, Elisabetta Boaretto3, Aldino Bondesan1, David Kuparadze4, Matteo Massironi2, Giovanni Monegato2 & Elena Rova5 1Dipartimento di Geografia “G. Morandini”, Università degli Studi di Padova, Italy 2Dipartimento di Geoscienze, Università degli Studi di Padova, Italy 3Helen Kimmel Center for Archaeological Science, Israel 4Caucasian Institute of Mineral Resources, Tbilisi, Georgia 5Dipartimento di Scienze dell’Antichità e del Vicino Oriente, Università Ca’ Foscari, Venezia, Italy Corresponding author: S. Furlani ABSTRACT: Furlani S. et al., Integrating archaeological and geomorphological data to evaluate the late-Holocene be- haviour of the Kartalini Basin (Georgia). (IT ISSN 0349-3356, 2011) A multidisciplinary approach has been used to evaluate the Late-Holocene modifications of the Kartalini basin (Georgia). Data from satellite images (Corona, Landsat, Russian aerial images, etc) and field surveying allowed to reconstruct the neotectonics in the area of Aradetis Orgora archaeological site. RIASSUNTO: Furlani S. et al., Comparazione di dati archeologici e geomorfologici per la valutazione del comportamento del bacino di Kartalini (Georgia) dal tardo-Olocene. (IT ISSN 0349-3356, 2011) Per studiare le modificazioni tardo Oloceniche del bacino di Kartalini (Georgia) è stato utilizzato un approccio multidisci- plinare. I dati provenienti dale immagini satellitari (Corona, Landsat, foto aeree russe, ecc) e I rilievi di campagna hanno permesso di ricostruire l’evoluzione neotettonica nell’area del sito archeologico di Aradetis Orgora. Key words: Geoarchaeology, active tectonics, late Holocene, Kura River, Georgia Parole chiave: Geoarcheologia, tettonica attiva, tardo Olocene, fiume Kura, Georgia Archaeological and geomorphological data are very useful to study Holocene river meandering because of the close relations between the pres- ence of water and human settlement. .In the mean- time, both the geomorphological evolution and the development of human settlements could be heav- ily conditioned by active tectonics effects (differential uplift, seismicity) In this study we aim to outline the late Holocene evolution of the Aradetis Orgora site, through the analysis of archaeological and morphological data,. The site is located in the Transcaucasian basin, historically characterized by active tectonics (ADAMIA et al. (1977), GAMKRELIDZE et al. (1986) e PHILIP et al. (1989), GUDJABIDZE, 2003) and it is poorly studied from a geomorphological point of view. 1. THE STUDY AREA The study area is located in the Shida Kartli Re- gion, a hundred kilometres West from Tbilisi. The Kura River crossed the area following a NNW-SSE direction, while the Liakhvi River represents an important tributary, which flows into the Kura near the modern city of Gori. The site of Aradetis Or- gora-Dedopolis Gora is located at the junction of a system of rivers (Kura, Western Prone, Eastern Prone). In particular, Aradetis Orgora lies on an isolated portion of the fluvial terrace (660 m a.s.l.), about 20 meters above the recent Kura floodplain (640 m a.s.l.). The site hosted an important settlement Roman/ Medieval in age, which wasexcavated by Georgian archaeologists under the direction of prof. Julon Gagoshidze (FÜRTWÄNGLER et al., 2008). The Classical Antiquity occupational levels are under- lain by a long sequence of earlier levels, which date back at least to the late 4th millennium BC, and are still virtually unexplored. 2. THE ARCHAEOLOGICAL SITE OF ARADETIS ORGORA The stratigraphic analysis was carried out on an exposed section on the southern sector of the ter- race slope, where the archaeological levels are superimposed to an alluvial stratigraphy related to the Kura River and its tributaries. Starting from the base, three main archaeological levels have been identified (Fig. 2): 1) An Early Bronze Age level characterized by a sequence of layers with abundant pottery and ceramics fragments of the Kura-Araxes and Be- deni periods (late 4th-mid 3rd millennium BC) in a muddy matrix. Radiocarbon dating of a wood 186 - 188 187 fragment from the base of the sequence yielded the age of the layer (±1σ 3025-2920 BC,). The level had been buried by a coarse alluvial event characterized by 1,5 m thick gravel body; 2) a Late Bronze Age layer characterized by muddy matrix with abundant pottery fragments; 3) a Roman Age and later layer at the topmost part of the site, characterized by abundant pottery and brick fragments. The presence of alluvial deposits between the two Bronze Age levels indicates a channel fluvial activ- ity on the terrace after 4300 BP. We suggest two possible hypothesis about the drainage evolution: a) The gravel layer covering the Early Bronze Age could represent the last phase of aggradation of Fig. 1 The study area / L’area di studio Fig. 1 The Aradetis Orgora archaeological site / Il sito archeologico di Aradetis Orgora Integrating archaeological and geomorphological data ... 188 Ms. received: Testo ricevuto il the Liakhvi alluvial fan and its progradation toward south. Subsequently the deepening of the Kura riverbed and its northward migration triggered the small incisions of the trenches surrounding the site. The Roman Age site was probably chosen for the isolated position derived from the geomor- phological evolution of the terrace. According to the present difference in elevation between the Liakhvi alluvial surface and the present Kura river- bed, the estimated total erosion is about 5 mm/ year, that is the result of a joined effect between river incision and active uplift of the area. b) The gravel layer may be ascribed to a palaeo- Kura (present Western Prone River) running wa- ters. After about 4000 BP, the Kura was forced to migrate toward south because of an active uplift of the Transcaucasian region. In this case, most of the 20 metres in the elevation difference between palaeo and present Kura should be related to tec- tonic activity. The importance of tectonic activity in the area is furthermore supported by the high seismicity of the Transcaucasian Basin (PHILIP et al., 1989; TRIEP et al., 1995) and the low fluvial erosion expected in a time span in which no great climatic changes oc- curred. Local uplift within the basin possibly related to a contractional step-over along the Borjomi- Kazbegi fault zone or the southern propagation of the Greater Caucasus belt. ACKNOWLEDGEMENTS We are kindly grateful to Mindia Jalabadze (Georgian National Museum), who accompanied us on the site during the 2009 season. The field survey in the Aradetis Orgora area took place in the framework of the “Georgian-Italian Shida Kartli Archaeological Project” (ROVA, 2008) of Ca’ Fo- scari University of Venice. This was funded by Ca’ Foscari University, Ministero degli Affari Esteri, and the Shelby White-Leon Levy Program for Archaeo- logical Publications. REFERENCES ADAMIA SH.A., LORDKIPANIDZE M.B. & ZAKARIADZE G.S. 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