Niki Evelpidou

Urban flood management.

1. Introduction Andras Szollosi-Nagy & Chris Zevenbergen 2. Land use & urban floods in developing countries Carlos Tucci & Adolfo Villanueva 3. Cities, lakes and floods: the case of the Green Hyderabad Project, India Joep Verhagen 4. Co-operation within Europe on flood management and spatial planning Roelof Moll 5. Spatial measures and instruments for flood risk reduction in selected EU countries - a quick scan Willem Oosterberg & Jasper Fiselier 6. Risk perceptance and preparedness and flood insurance Paul Baan 7. The role of private insurance companies in managing flood risks in the UK and Europe David Crichton 8. New strategies of damage reduction in urban areas proned to flood Erik Pasche & Timm Ruben Geissler 9. Flood resilience in the built environment: damage and repair Stephen Garvin 10. California climate change: hydrologic response, and flood forecasting Norman Miller Conclusions Andras Szollosi-Nagy & Chris Zevenbergen

Mapping Geomorphological Environments

Methodology-Techniques.- Fluvial Environments.- Coastal Environments.- Lacustrine Environments.- Glacial Environments.- Karstic Environments.- Volcanic Environments.- Aeolian Environments.- Surface Landforms.- Topography, Lithology and Tectonics.- Geomorphological Mapping (Case Studies).

Developing an Erosion Risk Map Using Soft Computing Methods (Case Study at Sifnos Island)

The erosional processes depend on various variables such as lithology, topography,drainage system, rock structure and climatic conditions. The quantitative evaluationof some of the above geological and geomorphological parameters is of primaryimportance for the purpose of developing erosion risk maps. These maps can becomeuseful tools for developing appropriate strategies on environmental protection, hazardassessment and regional planning.The island of Sifnos, in Cyclades, was chosen as a case study, where in the final map of the sub-basins of this island, erosion risk distribution is presented.

Holocene submerged shorelines on Theologos area (Greece)

Summary. Detailed mapping of coastline around Theologos area revealed the existence ofwell developed permanently submerged notches 75 10 cm below present mean sea level. Theregional occurrence of well preserved submerged tidal notches suggests their coseismic origin.The submergence of this Holocene shoreline possibly occurred at 1894 AD. Average submer-gence rate of 6.08 mm/yr may be estimated by a well preserved recumbent U-shaped notch.The retreating point depth suggests that the developing period of the notch might have beenof the order of as much as three thousand years.Several non in situ large rock blocks, containing marine fossils ( Lithophaga , Vermetids , Serpulids ) in growth position, seem to have been projected on the coast by a tsunami wave,which might have been caused by the same coseismic episode. Key words: notches, Sea-level changes, earthquake, tsunami, submergence rate 1 Introduction Tidal notches that usually undercut limestone cliffs in the mid-littoral zone are wellknown as precise sea-level indicators ( Pirazzoli 1986, 1996, 2005). In areas shelteredfrom wave action, elevated or submerged notches can be used to indicate former sea-level positions, with up to a decimeter confidence. The shape of the notch profilesmay also provide qualitative information on the rate of sea-level change and on tec-tonic movements.The aim of this paper is to use notches as sea level indicators to identify formershoreline positions in the area of Theologos and to show that their presence anddevelopment is associated with vertical movements of possible coseismic origin.In Section 2 the genesis of notch shapes is discussed, while in Section 3a briefpresentation of the geological setting and some archaeological and seismologicalinformation of the study area is presented. The methodology used is summarized inSection 4, while the main results obtained are presented and discussed in Sections 5and 6.2

Yria (western Naxos island, Greece): Sea level changes in Upper Holocene and palaeogeographical reconstruction

The Saint Georgios coastal zone, located at the W coast of Naxos, the largest island of the Central Aegean Sea, was investigated in order to determine the palaeo-geography, sea level changes and their effect to the palaeo-environment of western Naxos island and to human activity. Detailed geomorphological mapping, study of micropaleontological and sedimentological characteristics and dating analyses of the Late Holocene of St. Georgios coastal zone were conducted. To obtain information about the Holocene stratigraphy under the recent alluvial cover, three boreholes followed the detailed geomorphological mapping. Microfaunal analysis took place and five samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS and conventional radiocarbon techniques providing temporal control of the sediments. The sea-land interactions during Upper Holocene, in relation to the eustatic sea level oscillations, as well as the geomorphologic observations and analysis on deposited sediments, aims to reveal the palaeo-geographic evolution of the landscape and its impact on the archaeological sites. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 6144 BP have been verified.

Origin and Holocene Evolution of a Slightly Submerged Tidal Notch in the NE Adriatic

ABSTRACT Evelpidou, N.; Pirazzoli, P.A., and Spada, G., 2015. Origin and Holocene evolution of a slightly submerged tidal notch in the NE Adriatic. A puzzling, slightly submerged, single tidal notch has been reported from the carbonate coasts of the northeastern Adriatic Sea. This paper attempts to explain the origin and the recent evolution of this marine erosion feature and the reasons for its uniqueness in the late Holocene. After reviewing how tidal notches are usually formed, a comparison of recent measurements of bioerosion rates carried out in the area show that when the contribution of dissolution processes can be neglected, bioerosion rates of the deepening of tidal-notch profiles appear to be very low (often <0.1 mm/y) along the coasts of Istria, in contrast to higher rates (between 0.2 and 1.0 mm/y) generally reported in other Mediterranean areas. Such a low rate of bioerosion implies a long period favourable to tidal-notch development. Several glacial isostatic adjustment computations show that relative sea level changes in the area during the last few millennia may correspond to a period of equilibrium between the regional tectonic subsidence and hydro-isostatic emergence during which relative sea level changes were limited, permitting development of the tidal notch observed. The submergence of the notch is consistent with a coseismic subsidence in late Roman time. After this, a new tidal notch could not form at the present sea level because of the limited amount of local bioerosion and the relatively large rate of sea level rise.

The geochemistry of Boron-rich groundwater of the Karlovassi Basin, Samos Island, Greece

The upper Miocene of Karlovassi Basin, Samos Island, Greece, contain continental evaporites such as colemanite, ulexite, celestite, gypsum and thenardite. These evaporites are related with volcanic tuffs, diagenetically altered in a saline-alkaline lake environment. The aim of the present paper is to: a) define the impact of the already known and possible buried borates and other evaporites to the geochemistry of the hydrogeological system of Karlovassi Basin, and; b) to assess the correlation between surface and underground evaporite deposits considering the spatial changes in the concentrations of the examined physicochemical parameters. Fieldwork, laboratory measurements and literature data revealed elevated boron values (2136–33012 ⧎/L) in the central part of Karlovassi Basin. In the same area, high amounts of strontium, sodium, lithium and sulfates also occur. It is proposed that these ions originate from the leaching of evaporites and authigenic minerals such as the Sr-rich clinoptilolite and the boron-bearing potassium feldspar. Boron values are abnormally high for freshwater aquifers, and are indicative of the presence of buried evaporites in the basin with unknown significance.

Sea-Level Indicators

Because changes in sea level may have a great impact on the distribution of mineral resources, the exploration and exploiting of these resources should not ignore the changes in sea level that may have occurred in the past in the area considered. The study of relative sea-level changes is an essential element of ocean observation and technological advances are often necessary to improve this study that includes the determination of levels (elevation or depth), chronological estimations, and the identification of appropriate sea-level indicators.

Palaeogeographic Evolution of the Cyclades Islands (Greece) During the Holocene

The Cycladic islands are located in the central Aegean Sea (Greece) forming a partly submerged plateau separated into two parts: the eastern shallower one (Andros, Tinos, Mykonos, Naxos, Paros, Syros, Ios, Sikinos, Folegandros) which formed one big island (6.978 km2) at the end of the last glacial period; the western islands (Kea, Kythnos, Serifos, Sifnos, Milos) which remained separated during the same period. The eastern islands constitute an erosional plateau which is the end product of a Neogene palaeosurface that was partially submerged due to thinning of the crust during the Quaternary. The presence of numerous Neolithic sites both on land and submerged indicates the existence of an advanced civilization in the area for thousands of years. The location of the lost Atlantis could be found in this area probably between Naxos, Paros and Antiparos.

Internet GIS Development for Educational Purposes

Geographical Information Systems (GIS) are important tools for various scientific aspects. Especially sciences related to cartography and geographical analysis should definitely employ GIS technology. In this study an Internet-based GIS is presented that was developed on the MapXtreme platform. This application gives access to numerous web-users through a server that controls both analysis and data retrieval requests. It is a practical and economical method in order to introduce GIS to educational institutions. This Web GIS may operate through a local or wide area network and, apart from educational purposes, offers a low cost information exchange solution between vast numbers of users.