The island of Crete is situated near the front of an active plate margin. Therefore, it is of great interest in the framework of the International Continental Drilling Project (I.C.D.P.). A short review of the digital modelling methods, their applications in the geosciences and the associated advantages is also presented. The digital 3-dimensional geometric model of the geological structure of the Samaria Gorge region is based on the study of the stratigraphy and the tectonic evolution of the metamorphic rocks of the Plattenkalk group in SW Crete. Data from the geological map of Greece (Vatolakkos sheet, 1:50.000) and from the literature have been supplemented by geological mapping and structural analyses. In our study we applied interactive 3D CAD methods implemented in the integrated software package SURPAC2000. The surface geology has been draped over a digital elevation model of the topography in order to model the geometry of the subsurface structures. Two hypotheses about the geological structure of the region are examined: a) the one given by the existing geological map, which proposes a syncline structure and b) the one resulting from the combination of existing data, corrections carried out through repeated 3D simulations and new field observations. After distinguishing in the S of the study area the Trypali union, overthrusted on the Plattenkalk group, we propose an anticline structure with a NNE/SSW striking axis dipping to the NE.

Sustainable management of protected areas requires good knowledge of the entire system. Complicated natural systems require for their management the use of digital information systems,

The present paper aims to the understanding of the causes of the large-scale landslide that occurred at Tsakona area (SW Arcadia, Peloponnesus) during February 2003. This is the largest landslide that have ever effected the Greek National highway network as it entirely rubed out the new Megalopolis-Kalamata highway at a length of 200m. It took place at the western slopes of Drosovouni Mt., which exhibits an elogated shape of NE-SW direction. At the broader area of the slide three alpine formations of the Pindos unit occur which from lower to upper are: (i) the Jurassic radiolarites, (ii) the so called 1s t flysch and (iii) the Upper-Cretaceous pelagic limestones. The initial sliding took place inside the first two formations and the landslide moved more than 1,000 meters downward along the mountain slope at an E-W direction while its headscarp was near the tectonic contact between these formations and the upperlying pelagic limestones.In order to understand the causes of the landslide we carried out a detailed geological, morphotectonic, microtectonic and neotectonic study of the broader area. Additionally we constructed the structural contour map between the limestones nappe and the underlying formations. From all the aforementioned we suggested that the landslide occurred in a tectonically active area where the neotectonic deformation. Based on the above-mentioned studies, we have to mention the followings: The landslides occur in a site that the tectonic deformation is very intense. There were old landslides before the activation of the last one and before the study and construction of the highway. The constructors as well as the people that studied the area did not take into account the already existed landslides. It has to be mentioned that hydrogeological regime of the area is of great importance, as to the opposite slopes of the landslide in which occur the same formations like in the landslide area there is no landslide activity at least the last 100 years as indicated by the existing railway, due to the no occurrence of limestones above the radiolarites. From all the above mentioned it is clear that the tectonics - neotectonics affected the major area are the main factors involved to the initiation of the landslide, and the crossing of the landslide by the highway contributed to the reactivation together with the rains.