Article ID Journal Published Year Pages File Type
4685457 Geomorphology 2011 18 Pages PDF
Abstract

The geomorphological evolution of the Pliocene–Quaternary Auletta basin, a wide fault-bounded depression of the southern Apennines axial zone, Italy, was reconstructed using both DEM-based morphometric analysis and classical morphotectonic investigations. Morphotectonic analyses have been integrated with geological, structural and paleomagnetic data in order to reconstruct the Quaternary evolution of the area.The Auletta basin coincides with the lower valley of the Tanagro River and is filled by Pliocene to Pleistocene marine and continental sediments. The strike of the basin is N120–130°, according to the main fault systems of the area.Long-term landscape evolution results from interaction and feedback of geomorphic stages with the morphogenesis of erosional land surfaces alternating with tectonic pulses in which also block-tectonic rotation occurred. The ages of the morphological de-activation of such terraced surfaces have been roughly defined on the grounds of their morpho-stratigraphic relationships with Pliocene and Quaternary deposits, and better constrained by radiometric dating. Tectonic tilting has been established from morphological relationships between rotated blocks related to the activity of the Alburni fault line and the several generations of erosional and depositional land surfaces. The stratigraphic, structural, paleomagnetic and geomorphological data presented here suggest that the studied basin appears to have a more complex tectonic evolution than an extensional graben. Transtensional tectonics along NW–SE striking, listric faults of the Alburni margin system created the depression since Pliocene times, whereas extensional tectonics plays a key role in the middle to late Pleistocene morphotectonic evolution of the basin. This work demonstrates the usefulness of an integrated analysis in order to extract information on tectonic activity and landscape evolution in the Auletta basin, as an example for other study areas.

► We reconstructed the morphotectonic evolution of a structural basin in southern Italy. ► Stratigraphic, paleomagnetic and geomorphological data are furnished. ► Basin evolution is constrained by relationships among landforms, deposits and faults. ► The activity of the master fault controlled the development of rotated landforms. ► The basin is more complex than an extensional graben.

Related Topics
Physical Sciences and Engineering Earth and Planetary Sciences Earth-Surface Processes
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