Multivariate Statistical Analysis in the Assessment of Hydrochemistry of the Northern Korinthia Prefecture Alluvial Aquifer System (Peloponnese,Greece)

The application of multivariate statistical analyses of hydrochemical data has proved to bemost successful in the assessment of groundwater hydrochemistry, especially in situationswhere numerous samples are available. Fifteen (15) hydrochemical parameters were considered(pH, E.C., T.D.S., T.H, Ca, Mg, Na, K, HCO₃, Cl, SO₄, NO₃, NO₂, NH₄, PO₄) in 131 samplescollected from the alluvial aquifer of NE Korinthia, during May 1997. Simple and multipleregression, factor, and trend-surface analyses were applied in order to examine the importance ofeach parameter, investigate correlations among them, and separate them into groups. Statisticalfactors were selected and their geographical distribution was mapped. It was concluded thatuse of such methods reveal the prevailing evolutionary mechanisms of the studied system,thus enabling accurate and relatively quick hydrochemical assessments.     

The Contribution of Landslide Susceptibility Factors Through the Use of Rock Engineering System (RES) to the Prognosis of Slope Failures: An Application in Panagopoula and Malakasa Landslide Areas in Greece

This paper presents an application of the rock engineering system (RES) in an attempt to assess the proper landslide parameters and estimate the instability index, using two disastrous landslides in Greece which took place in Panagopoula (1971) and Malakasa (1995). RES has been developed by Hudson (Rock engineering systems: theory and practice. Ellis Horwood Limited, 1992) to determine interaction of a number of parameters in rock engineering design and calculate instability index for rock slopes. In this paper, an attempt is made to prove, how RES can be implemented in large-scale instability areas where natural slopes are associated with a variety of geomaterials (soils, rocks, weathering mantle, etc.), by selecting each time the most appropriate parameters that are relevant to the ad hoc potential slope failure and which can be quantified easiest than those of time and money consuming ones. RES approach allows the utilization of those parameters which are particularly active at the site, evaluates the importance of their interactions, taking into account the particular problems at any investigated site. The instability index for both study areas were calculated and found 89.47 for Panagopoula site and 81.59 for Malakasa (out of 100). According to the classification for landslide susceptibility by Brabb et al. (Landslide susceptibility in San Mateo County, California, 1972), both the examined case studies are classified as landslides, approving their existence as two serious slope failures. Thus, RES could be a simple and efficient tool in calculating the instability index and consequently in getting the prognosis of a potential slope failure in landslide susceptible areas, for land use and development planning processes.