Abstract:
In the coastal karstic area of the southeastern Murge (Apulia, Italy) changes in sea level, due to vertical tectonic movement and/or global climatic phenomena, generated morphological effects both at the surface (marine terraces) and underground (variations of karstic base level), so by integrating and comparing observations of surface and subsurface morphology, a more reliable picture of the structural and palaeogeographical evolution was obtained. The calculation of topographic gradients and spectral analysis of the topographic surface was applied in order to identify the morphological remnants left by coastal terraces corresponding to palaeo coastlines. Using these methods it is possible to recognize small morphological scarps which otherwise would be masked by major structures. The results obtained were compared with the altimetric distribution of karstic cave bottom surfaces which were examined in order to determine karstic base levels. Some discrepancies between the two kinds of observations can be explained in terms of rate of sea level variation (produced by the tectonic tilting of the Apulian foreland). In some periods this rate was probably compatible with the rate of the surface processes but not with that of underground processes