Rend. Online Soc. Geol. It., Vol. 21 (2012), pp. 1136-1138, 2 figs. © Società Geologica Italiana, Roma 2012 1136 Key words: geomorphology, palaeosurface, southern Italy. INTRODUCTION Long-term landscape evolution of an orogen results from the interaction between tectonic and geomorphological processes, largely controlled by regional uplift, fault activity and climate changes (WILLETT, 1999; WILLETT & BRANDON, 2002; WOBUS et alii, 2003; SCHIATTARELLA et alii, 2006; BISHOP, 2007). In the last decade, there has been a rise of interest particularly on the role of climate changes in landscape evolution (WHIPPLE et alii, 1999; BONNET & CRAVE, 2003; BURBANK et alii, 2003; WHIPPLE, 2009). In tectonically active areas characterized by a complex morpho-structural evolution, both relict and active landforms coexist as a result of exogenic vs. endogenic processes. Ancient landforms such as palaeo- landsurfaces represent non-equilibrium features (cf. BRACKEN & WAINWRIGHT, 2006) resulting by surface uplift and subsequent degradation due to erosion. The term palaeosurface denotes any identifiable surface of demonstrable antiquity, often characterized by gentle topography represented by relics of an ancient erosional land surface, that evolved in response to particular combination of geomorphological processes (WIDDOWSON, 1997; BONOW et alii, 2006). The physical correlation of discrete remnants of palaeosurfaces allows to recognize extension and morphology of such ancient planation surfaces related to a former base level of the erosion (i.e. not in accordance with present morpho- climatic conditions), and they are identified in terms of attitude (i.e. characterized by little slope angles, not exceeding few degrees) and on the grounds of several markers of geomorphic processes acting in the past. The reconstruction and dating of ancient land surface can provide useful information on morphotectonic evolution, whereas the nature of subsequent modifications by changing erosional and weathering regimes can reveal key aspects of subsequent environmental change (BORGER, 1997; SCHOENBOHM et alii, 2004). Hung land surfaces (i.e. terraced surfaces suspended with regard to the present-day thalwegs) are also markers of regional-scale neotectonic deformation and provide information on the rate and timing of uplift and erosion (SCHIATTARELLA et alii, 2006, 2008; MARTINO et alii, 2009). Recently, the relation between morphotectonic features and the fractal dimension of topography of Taiwan has been explored as well (SUNG & CHEN, 2004). It has been found that the fractal morphology may reflect some subtle changes in topographic properties of a landscape sculpted by surface processes, which in turn are influenced by tectonic activities. This property is perhaps more diffused than reported in that paper, because a fractal behaviour was also found in studies of coastal and fluvial features (RIGON et alii, 1994; TURCOTTE, 1999; DE PIPPO et alii, 2004; RINALDO et alii, 2006). The Hack’s law relating the upstream length and the total drainage area at a given location is another evidence of fractal geometry in fluvial landforms. These statistical properties of river basins are irrespective of age even if real drainage basins evolve on a long-term time-scale. Furthermore, it was reported that the fractal dimension of the drainage network can also provide a method for assessing the degree of tectonic control on the geometry of fluvial networks (DEL MONTE et alii, 1999). The purpose of this study is to better define the age of the summit palaeosurface of the southern Italian Apennines (i.e. “Paleosuperficie” Auctt.) by both morphostratigraphic and AFTA dating methods, with the aims of refining its use as a morphotectonic marker and distinguishing climate and tectonic contributions in landscape evolution. DISCUSSION The top of the mountains of southern Italy are often featured by erosional flat landforms representing the remnants of a wide palaeosurface attributed to the late Pliocene – Quaternary boundary. Apatite fission-track analyses collected in the last years furnished new chronological constrains in terms of its absolute age: this kind of data has been here used in combination with geology and morphotectonics to better define its evolution. AFT data from rocks belonging to different tectonic units of the axial zone of the southern Apennines (ALDEGA et alii,; MAZZOLI et alii, 2008) indicate a concordant final cooling age of ca 2.5-2.6 Ma (average value, SCHIATTARELLA et alii, 2009; GIOIA et alii, 2011), suggesting a widespread exhumation during the late Pliocene. This relatively young exhumation is likely related to erosional Age and properties of the summit palaeosurface of southern Italy MARCELLO SCHIATTARELLA (*), SALVATORE IVO GIANO (*) & DARIO GIOIA (°) _________________________ (*) Dipartimento di Scienze Geologiche, Università della Basilicata, Potenza, Italia (°) Istituto Istituto per i Beni Archeologic e Monumentali, Consiglio Nazionale delle Ricerche (CNR-IBAM), Contrada Santa Loja, I-85050 Tito Scalo (Potenza), Italia