The Alburni Mts. area represents one of the most important karst features of southern Italy, with about 250 registered caves localized within Meso-Cenozoic carbonates of the Campania- Lucania platform. The Alburni ridge consists of a 1500 m-thick, SW dipping monocline locally overlain by Tertiary flysch and Quaternary fluvial-lacustrine sediments nowadays mainly localized within elongated, fault-bounded, small-scale halfgrabens. The whole carbonate massif is crosscut be two main fault sets, respectively trending NW-SE and NE-SW. The former faults are mainly characterized by normal displacements, whereas the latter ones by transtensional displacements with right-lateral components of slip. Minor fault sets with orientations ENE-WSW and NNW-SSE are also present.Although the Alburni carbonate massif has been investigated since the early ‘70s, both its geological setting and karst architecture are poorly known. Previous studies showed the close correlation between karst development and faults. Our preliminary field results, after detailed surface and speleological surveys, not only confirm this correlation but also point out to the role played by small-scale faults and pervasive jointing. In fact, karsts mainly localize along meso-scale fault zones and joint zones, as well as along bedding planes. The statistical analysis of 243 investigated caves is consistent with the cave end levels grouped in four different altitude ranges (450-500, 800-850, 1050-1100 and 1300-1350 meters a.s.l., respectively).The aforementioned data suggest a lowering of the erosion base level due to tectonic uplift and/or different fracturing state of the subsurface carbonates. In order to evaluate the role played by tectonic uplift on karst development, a geomorphological analysis of the several erosional surfaces, as well as mapping of all travertine deposits, cropping out in the surrounding areas of the Alburni Mts. is currently carried out. Regarding the control exerted by smallscale faults and joint zones on karst, the results of an ongoing investigation of the intensity, spatial distributions and overall architecture of these structural features exposed at surface within the Cretaceous carbonates will allow us to decipher the possible control exerted by deformation on subsurface fluid flow.
Karst system evolution and the role of faulting: the case of the Alburni Mts
PARISE, Mario;
2013-01-01
Abstract
The Alburni Mts. area represents one of the most important karst features of southern Italy, with about 250 registered caves localized within Meso-Cenozoic carbonates of the Campania- Lucania platform. The Alburni ridge consists of a 1500 m-thick, SW dipping monocline locally overlain by Tertiary flysch and Quaternary fluvial-lacustrine sediments nowadays mainly localized within elongated, fault-bounded, small-scale halfgrabens. The whole carbonate massif is crosscut be two main fault sets, respectively trending NW-SE and NE-SW. The former faults are mainly characterized by normal displacements, whereas the latter ones by transtensional displacements with right-lateral components of slip. Minor fault sets with orientations ENE-WSW and NNW-SSE are also present.Although the Alburni carbonate massif has been investigated since the early ‘70s, both its geological setting and karst architecture are poorly known. Previous studies showed the close correlation between karst development and faults. Our preliminary field results, after detailed surface and speleological surveys, not only confirm this correlation but also point out to the role played by small-scale faults and pervasive jointing. In fact, karsts mainly localize along meso-scale fault zones and joint zones, as well as along bedding planes. The statistical analysis of 243 investigated caves is consistent with the cave end levels grouped in four different altitude ranges (450-500, 800-850, 1050-1100 and 1300-1350 meters a.s.l., respectively).The aforementioned data suggest a lowering of the erosion base level due to tectonic uplift and/or different fracturing state of the subsurface carbonates. In order to evaluate the role played by tectonic uplift on karst development, a geomorphological analysis of the several erosional surfaces, as well as mapping of all travertine deposits, cropping out in the surrounding areas of the Alburni Mts. is currently carried out. Regarding the control exerted by smallscale faults and joint zones on karst, the results of an ongoing investigation of the intensity, spatial distributions and overall architecture of these structural features exposed at surface within the Cretaceous carbonates will allow us to decipher the possible control exerted by deformation on subsurface fluid flow.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
