bluuebunny/crossref_metadata_2025 huggingface dataset:
Geophysical and stratigraphical research into deep groundwater and intruding seawater in the mediterranean area (the Salento Peninsula, Italy)
Authors: Margiotta S. , Negri S.
Published: April 2010

Abstract. Geological, geophysical and hydrological surveys were performed in an area between Lecce to the North and Otranto to the South on the Lower Adriatic coast of Italy in order to verify the ``state of health'' of the ground water in the deep aquifer, which is characterised by Mesozoic carbonatic formations and is permeable due to fracturing and karstic phenomena. This area was chosen because it is highly urbanised, and contains many wells, some of which were intensively studied from a geological and hydro-geological point of view in 1987. The first phase of the research consisted of a stratigraphical and geological study, based on geological surveys of the surface and the subsoil by direct observation of borehole cores and the collection and analysis of existing stratigraphical data on wells in the area. The stratigraphical and hydrogeological data are kept in the archives of local agencies. The collected data were organised in a single database managed by an appropriate software (ARCVIEW). Numerous geological cross sections of the territory were studied in order to characterise the subsoil. Subsequently, multi-parameter surveys (O2, pH, temperature, TDS, conductivity) were carried out on the water-column of certain wells selected from those studied in 1987. This was to verify possible changes in the state of the groundwater since 1987. The surveys were carried out in two different periods (May and September) in order to identify potential differences between rainy and dry periods. Moreover, electrical tomography was used to characterise the various subsurface geological formations and possible saline water intrusion where direct information collected from the wells was lacking. From the research conducted it was possible to effect a stratigraphical characterisation of the subsoil and to verify overexploitation of the water resources resulting from the increasing number of wells, and the consequent deterioration of the aquifer due to saline water intrusion. The research also confirms the validity of geophysical methods for the study of hydro-geological issues.
Shallow and deep landslides induced by rainfall in the Lisbon region (Portugal): assessment of relationships with the North Atlantic Oscillation
Authors: Zêzere J. L. , Trigo R. M. , Trigo I. F.
Published: April 2010

Abstract. The aim of this study is to assess the impact of the North Atlantic Oscillation (NAO) on both the winter precipitation and the temporal occurrence of different landslide types in Portugal. The analysis is applied to five sample areas located just north of Lisbon, the capital of Portugal. These sites are particularly relevant because actual dates of most of the recent landslide events are known but also because the landslides occurred in a suburban area with growing urbanization pressure. Results show that the large inter-annual variability of winter precipitation observed in western Iberia, i.e. Portugal and parts of Spain, is largely modulated by the NAO mode. In particular, precipitation falling in Portugal between November and March presents a correlation coefficient of R=–0.66 with the NAO index. Precipitation distribution for the reference rain gauge in the study area reveals that the probability of a wet month to occur is much higher for low NAO index composites than for the corresponding high NAO index composite. It is shown that this control, exerted by NAO on the precipitation regime, is related to corresponding changes in the associated activity of North-Atlantic storm tracks that affect the western Iberia. Landslide activity in the study area is related to both intense, short duration precipitation events (1–15 days) and long-lasting rainfall episodes (1–3 months). The former events trigger shallow translational slides while the later episodes are usually associated with deeper and larger slope movements. This second group of landslides is shown to be statistically associated with the 3-month average of the NAO index.
Evolution of natural risk: research framework and perspectives
Authors: Hufschmidt G. , Crozier M. , Glade T.
Published: April 2010

Abstract. This study presents a conceptual framework for addressing temporal variation in natural risk. Numerous former natural risk analyses and investigations have demonstrated that time and related changes have a crucial influence on risk. For natural hazards, time becomes a factor for a number of reasons. Using the example of landslides to illustrate this point, it is shown that: 1. landslide history is important in determining probability of occurrence, 2. the significance of catchment variables in explaining landslide susceptibility is dependent on the time scale chosen, 3. the observer's perception of the geosystem's state changes with different time spans, and 4. the system's sensitivity varies with time. Natural hazards are not isolated events but complex features that are connected with the social system. Similarly, elements at risk and their vulnerability are highly dynamic through time, an aspect that is not sufficiently acknowledged in research. Since natural risk is an amalgam of hazard and vulnerability, its temporal behaviour has to be considered as well. Identifying these changes and their underlying processes contributes to a better understanding of natural risk today and in the future. However, no dynamic models for natural risks are currently available. Dynamic behaviour of factors affecting risk is likely to create increasing connectivity and complexity. This demands a broad approach to natural risk, since the concept of risk encapsulates aspects of many disciplines and has suffered from single-discipline approaches in the past. In New Zealand, dramatic environmental and social change has occurred in a relatively short period of time, graphically demonstrating the temporal variability of the geosystem and the social system. To understand these changes and subsequent interactions between both systems, a holistic perspective is needed. This contribution reviews available frameworks, demonstrates the need for further concepts, and gives research perspectives on a New Zealand example.
Multidisciplinary co-operation in building design according to urbanistic zoning and seismic microzonation
Authors: Bostenaru Dan M.
Published: April 2010

Abstract. Research and practice in seismology and urban planning interfere concerning the impact of earthquakes on urban areas. The roles of sub-area wide or typological divisions of the town were investigated with the methodology of regression, regarding their contribution to urban earthquake risk management. The inductive data set comprised recovery, preparedness, mitigation and resilience planning. All timely constituted planning types are refound today as layers, as the zoning results are used by differently backgrounded actors: local authorities, civil protection, urban planners, civil engineers. In resilience planning, the urban system is complexly theoretised, then integratedly approached. The steady restructuring process of the urban organism is evident in a dynamic analysis. Although expressed materially, the "urban-frame" is realised spiritually, space adaptation being also social. A retrospective investigation of the role of resilient individual buildings within the urban system of Bucharest, Romania, was undertaken, in order to learn systemic lessons considering the street, an educational environment. (In)formation in the study and decision making process stay in a reciprocal relationship, both being obliged in the (in)formation of the public opinion. For a complete view on resilience, both zoning types, seismic and urbanistic, must be considered and through their superposition new sub-area wide divisions of the town appear, making recommendations according to the vulnerability of the building type.
Temporal stereophotogrammetric analysis of retrogressive thaw slumps on Herschel Island, Yukon Territory
Authors: Lantuit H. , Pollard W. H.
Published: April 2010

Abstract. The western Canadian Arctic is identified as an area of potentially significant global warming. Thawing permafrost, sea level rise, changing sea ice conditions and increased wave activity will result in accelerated rates of coastal erosion and thermokarst activity in areas of ice-rich permafrost. The Yukon Coastal Plain is widely recognized as one of the most ice-rich and thaw-sensitive areas in the Canadian Arctic. In particular, Herschel Island displays extensive coastal thermokarst. Retrogressive thaw slumps are a common thermokarst landform along the Herschel Island coast that have been increasing in both frequency and extent have in recent years due to increased thawing of massive ground ice and coastal erosion. The volume of sediment and ground ice eroded by retrogressive slump activity and the potential release of climate change related materials like organic carbon, carbon dioxide and methane are largely unknown. The remote setting of Herschel Island, and the Arctic in general, make direct observation of this type of erosion and the analysis of potential climate feedbacks extremely problematic. Remote sensing provides possibly the best solution to this problem. This study looks at two retrogressive thaw slumps located on the western shore of Herschel Island and using stereophotogrammetric methods attempts to (1) develop the first three-dimensional geomorphic analysis of this type of landform, and (2) provide an estimation of the volume of sediment/ground ice eroded through back wasting thermokarst activity. Digital Elevation Models were extracted for the years 1952, 1970 and 2004 and validated using data collected in the field using Kinematic Differential Global Positioning System. Estimates of sediment volumes eroded from retrogressive thaw slumps were found to vary greatly. In one case the total volume of material lost for the 1970–2004 period was approximately 1560000m3. The estimated volume of sediment alone was 360000m3. The temporal analysis of the DEMs suggest that second generation retrogressive thaw slump activity within the floor of a large polycyclic retrogressive thaw slump is possible.
Contribution of multi-temporal remote sensing images to characterize landslide slip surface ‒ Application to the La Clapière landslide (France)
Authors: Casson B. , Delacourt C. , Allemand P.
Published: April 2010

Abstract. Landslide activity is partly controlled by the geometry of the slip surface. This activity is traduced at the surface by displacements and topographic variations. Consequently, multi-temporal remote sensing images can be used in order to characterize the geometry of landslide slip surface and its spatial and temporal evolution. Differential Digital Elevation Models (DEMs) are obtained by subtracting two DEMs of different years. A method of multi-temporal images correlation allows to generate displacement maps that can be interpreted in terms of velocity and direction of movements. These data are then used to characterize qualitatively the geometry of the slip surface of the la Clapière landslide (French Southern Alps). Distribution of displacement vectors and of topographic variations are in accordance with a curved slip surface, characterizing a preferential rotational behaviour of this landslide. On the other hand, a spatial and temporal evolution of the geometry of the slip surface is pointed out. Indeed, a propagation of the slip surface under the Iglière bar, in the W part of the landslide, is suspected and can be linked to the acceleration of the landslide in 1987. This study shows the high potential of multi-temporal remote sensing images for slip surface characterization. Although this method could not replace in situ investigations, it can really help to well distribute geophysical profiles or boreholes on unstable areas.
History and present state of the Slano Blato landslide
Authors: Logar J. , Fifer Bizjak K. , Kočevar M. , Mikoš M. , Ribičič M. , Majes B.
Published: April 2010

Abstract. The Slano Blato landslide is more than 1290m long, 60 to 200m wide and 3 to 11m deep with a volume of about 700000m3. It is located in the Eocene flysch region of western Slovenia with a limestone overthrust in the direct vicinity, above the landslide. The landslide moves mainly as a viscous earth flow with occurrences of rapid mud flows. In dry periods or in freezing conditions it behaves as a group of several slow to moderate landslides. The landslide follows the course of the Grajšček stream and is presently only 220m away from Lokavec village. The landslide was first mentioned about 200 years ago. In 1887 it flowed as a liquid flow and reached and destroyed the main road in the valley 2 km away. The Austro-Hungarian monarchy sent one engineer to the site and 17 years later the slide was remediated with a series of torrential check dams. The monarchy prohibited any construction works in the influence area of the landslide. During the 20th century the region changed from Austrian, Italian, Yugoslav, and finally to Slovenian government in 1991. The relevant Austrian measures and decisions were forgotten during the course of the years, and building permits were issued after the World War II to local people who populated the part of the landslide influence area. Simultaneously, regular maintenance of the excellent past engineering works was neglected. In November 2000 a large landslide of mud and debris was triggered again and it still presents a danger to the relatively new residential houses today. At present, the village is protected against mudflows by a small rockfill dam and by the regulation of the stream bed. In rainy periods removal of mud is necessary to maintain safe conditions for the village. The paper discusses the geological, hydrogeological, hydrological and geotechnical conditions for the occurrence of the Slano Blato landslide. The primary reasons for the Slano blato landslide are the geological and hydrogeological conditions just beneath the overthrust of a Triassic limestone plateau over the Eocene flysch of Vipava valley. The direct reason for triggering the earth flow in 2000 was the intensive precipitation. During the course of years the precipitation threshold for earth flow movements has diminished. The landslide has to be remediated for two main reasons – (1) the village below the landslide is endangered, and (2) the landslide is still advancing retrogressively and laterally. The foreseen permanent remediation measures that are currently under construction are briefly presented.
Frost damage of bricks composing a railway tunnel monument in Central Japan: field monitoring and laboratory simulation
Authors: Thomachot C. , Matsuoka N. , Kuchitsu N. , Morii M.
Published: April 2010

Abstract. Bricks of tunnels and bridges of Usui Pass railway (Japan) exposed to north are subject to frost damage. Average depth of erosion due to detachment of angular blocks is around 1-1.5 cm. In order to assess this weathering and to understand its mechanism, an experimental study was carried out in the field and laboratory. Field monitoring showed the combination of seasonal and diurnal freezing with a maximum of heave when the freezing front reached 5 cm depth. Bricks taken from the site were submitted to unidirectional freezing at capillary and vacuum saturation in the laboratory. Results showed that frost damage of bricks was favoured by high saturation level and repetition of freeze-thaw cycles.
Avalanche related damage potential - changes of persons and mobile values since the mid-twentieth century, case study Galtür
Authors: Keiler M. , Zischg A. , Fuchs S. , Hama M. , Stötter J.
Published: April 2010

Abstract. When determining risk related to natural hazard processes, many studies neglect the investigations of the damage potential or are limited to the assessment of immobile values like buildings. However, persons as well as mobile values form an essential part of the damage potential. Knowledge of the maximum number of exposed persons in an endangered area is of great importance for elaborating evacuation plans and immediate measures in case of catastrophes. In addition, motor vehicles can also be highly damaged, as was shown by the analysis of avalanche events. With the removal of mobile values in time as a preventive measure this kind of damage can be minimised. This study presents a method for recording the maximum number of exposed persons and monetarily assessing motor vehicles in the municipality of Galtür (Tyrol, Austria). Moreover, general developments of the damage potential due to significant socio-economic changes since the mid-twentieth century are pointed out in the study area. The present situation of the maximum number of persons and mobile values in the official avalanche hazard zones of the municipality is described in detail. Information on the number of persons is derived of census data, tourism and employment statistics. During the winter months, a significant increase overlaid by strong short-term fluctuation in the number of persons can be noted. These changes result from a higher demand of tourism related manpower as well as from varying occupancy rates. The number of motor vehicles in endangered areas is closely associated to the number of exposed persons. The potential number of motor vehicles is investigated by means of mapping, statistics on the stock of motor vehicles and the density distribution. Diurnal and seasonal fluctuations of the investigated damage potential are pointed out. The recording of the number of persons and mobile values in endangered areas is vital for any disaster management.
Quantitative expression on drought magnitude and disaster intensity
Authors: Feng L. H. , Zhang X. C.
Published: April 2010

Abstract. According to the calculation of wind scale and earthquake magnitude, this paper puts forward the concept of drought magnitude and disaster intensity and lays out a new method by quantitative calculation. Drought magnitude is the quantitative index that describes the scale of a drought, and disaster intensity of drought is the quantitative index to describe the loss caused by a drought. Both indices have many theoretical and practical advantages with definable concepts and simple applications; therefore they are of important practical significance.
Remote sensing of glacier- and permafrost-related hazards in high mountains: an overview
Authors: Kääb A. , Huggel C. , Fischer L. , Guex S. , Paul F. , Roer I. , Salzmann N. , Schlaefli S. , Schmutz K. , Schneider D. , Strozzi T. , Weidmann Y.
Published: April 2010

Abstract. Process interactions and chain reactions, the present shift of cryospheric hazard zones due to atmospheric warming, and the potential far reach of glacier disasters make it necessary to apply modern remote sensing techniques for the assessment of glacier and permafrost hazards in high-mountains. Typically, related hazard source areas are situated in remote regions, often difficult to access for physical and/or political reasons. In this contribution we provide an overview of air- and spaceborne remote sensing methods suitable for glacier and permafrost hazard assessment and disaster management. A number of image classification and change detection techniques support high-mountain hazard studies. Digital terrain models (DTMs), derived from optical stereo data, synthetic aperture radar or laserscanning, represent one of the most important data sets for investigating high-mountain processes. Fusion of satellite stereo-derived DTMs with the DTM from the Shuttle Radar Topography Mission (SRTM) is a promising way to combine the advantages of both technologies. Large changes in terrain volume such as from avalanche deposits can indeed be measured even by repeat satellite DTMs. Multitemporal data can be used to derive surface displacements on glaciers, permafrost and landslides. Combining DTMs, results from spectral image classification, and multitemporal data from change detection and displacement measurements significantly improves the detection of hazard potentials. Modelling of hazardous processes based on geographic information systems (GIS) complements the remote sensing analyses towards an integrated assessment of glacier and permafrost hazards in mountains. Major present limitations in the application of remote sensing to glacier and permafrost hazards in mountains are, on the one hand, of technical nature (e.g. combination and fusion of different methods and data; improved understanding of microwave backscatter). On the other hand, better dissemination of remote sensing expertise towards institutions involved in high-mountain hazard assessment and management is needed in order to exploit the large potential of remote sensing in this field.
Monitoring soil wetness variations by means of satellite passive microwave observations: the HYDROPTIMET study cases
Authors: Lacava T. , Greco M. , Di Leo E. V. , Martino G. , Pergola N. , Sannazzaro F. , Tramutoli V.
Published: April 2010

Abstract. Soil moisture is an important component of the hydrological cycle. In the framework of modern flood warning systems, the knowledge of soil moisture is crucial, due to the influence on the soil response in terms of infiltration-runoff. Precipitation-runoff processes, in fact, are related to catchment's hydrological conditions before the precipitation. Thus, an estimation of these conditions is of significant importance to improve the reliability of flood warning systems. Combining such information with other weather-related satellite products (i.e. rain rate estimation) might represent a useful exercise in order to improve our capability to handle (and possibly mitigate or prevent) hydro-geological hazards. Remote sensing, in the last few years, has supported several techniques for soil moisture/wetness monitoring. Most of the satellite-based techniques use microwave data, thanks to the all-weather and all-time capability of these data, as well as to their high sensitivity to water content in the soil. On the other hand, microwave data are unfortunately highly affected by the presence of surface roughness or vegetation coverage within the instantaneous satellite field of view (IFOV). Those problems, consequently, strongly limit the efficiency and the reliability of traditional satellite techniques. Recently, using data coming from AMSU (Advanced Microwave Sounding Unit), flying aboard NOAA (National Oceanic and Atmospheric Administration) satellites, a new methodology for soil wetness estimation has been proposed. The proposed index, called Soil Wetness Variation Index (SWVI), developed by a multi-temporal analysis of AMSU records, seems able to reduce the problems related to vegetation and/or roughness effects. Such an approach has been tested, with promising results, on the analysis of some flooding events which occurred in Europe in the past. In this study, results achieved for the HYDROPTIMET test cases will be analysed and discussed in detail. This analysis allows us to evaluate the reliability and the efficiency of the proposed technique in identifying different amounts of soil wetness variations in different observational conditions. In particular, the proposed indicator was able to document the actual effects of meteorological events, in terms of space-time evolution of soil wetness changes, for all the analysed HYDROPTIMET test cases. Moreover, in some circumstances, the SWVI was able to identify the presence of a sort of "early" signal in terms of soil wetness variations, which may be regarded as a timely indication of an anomalous value of soil water content. This evidence suggests the opportunity to use such an index in the pre-operational phases of the modern flood warning systems, in order to improve their forecast capabilities and their reliability.
Sensitivity of quantitative precipitation forecasts to boundary layer parameterization: a flash flood case study in the Western Mediterranean
Authors: Zampieri M. , Malguzzi P. , Buzzi A.
Published: April 2010

Abstract. The "Montserrat-2000" severe flash flood event which occurred over Catalonia on 9 and 10 June 2000 is analyzed. Strong precipitation was generated by a mesoscale convective system associated with the development of a cyclone. The location of heavy precipitation depends on the position of the cyclone, which, in turn, is found to be very sensitive to various model characteristics and initial conditions. Numerical simulations of this case study using the hydrostatic BOLAM and the non-hydrostatic MOLOCH models are performed in order to test the effects of different formulations of the boundary layer parameterization: a modified version of the Louis (order 1) model and a custom version of the E-ℓ (order 1.5) model. Both of them require a diagnostic formulation of the mixing length, but the use of the turbulent kinetic energy equation in the E-ℓ model allows to represent turbulence history and non-locality effects and to formulate a more physically based mixing length. The impact of the two schemes is different in the two models. The hydrostatic model, run at 1/5 degree resolution, is less sensitive, but the quantitative precipitation forecast is in any case unsatisfactory in terms of localization and amount. Conversely, the non-hydrostatic model, run at 1/50 degree resolution, is capable of realistically simulate timing, position and amount of precipitation, with the apparently superior results obtained with the E-ℓ parameterization model.
Investigation of ULF magnetic anomaly during Izu earthquake swarm and Miyakejima volcano eruption at summer 2000, Japan
Authors: Kotsarenko A. , Molchanov O. , Hayakawa M. , Koshevaya S. , Grimalsky V. , Pérez Enríquez R. , López Cruz-Abeyro J. A.
Published: April 2010

Abstract. Results of the ULF electromagnetic emission during the Izu, 2000 earthquake (EQ) swarm and Miyake volcano eruptions during the summer period of 2000 are presented and analyzed. The analysis of the obtained data has been performed in 3 main directions: traditional statistical analysis, i.e. analysis of time dynamics of spectral density, polarization ratios and their derivatives, Principal Component Analysis, and Fractal Analysis. The statistical characteristics were studied at different frequency sub-bands in a frequency range 10-3-0.3 Hz. These methods of data processing are described and the obtained results are illustrated and discussed. Some peculiarities of the obtained results such as the rise of the second principal component and the rise of the fractal index can be interpreted as possible short-time precursors.
Earthquake lights and rupture processes
Authors: Losseva T. V. , Nemchinov I. V.
Published: April 2010

Abstract. A physical model of earthquake lights is proposed. It is suggested that the magnetic diffusion from the electric and magnetic fields source region is a dominant process, explaining rather high localization of the light flashes. A 3D numerical code allowing to take into account the arbitrary distribution of currents caused by ground motion, conductivity in the ground and at its surface, including the existence of sea water above the epicenter or (and) near the ruptured segments of the fault have been developed. Simulations for the 1995 Kobe earthquake were conducted taking into account the existence of sea water with realistic geometry of shores. The results do not contradict the eyewitness reports and scarce measurements of the electric and magnetic fields at large distances from the epicenter.
Anomalies of LF signal during seismic activity in November–December 2004
Authors: Rozhnoi A. A. , Solovieva M. S. , Molchanov O. A. , Hayakawa M. , Maekawa S. , Biagi P. F.
Published: April 2010

Abstract. A signal transmitted by Japan Time Standard LF station (40 kHz, Fukushima prefecture) and recorded in Petropavlovsk-Kamchatski (Russia) is analyzed during a time interval from 1 July 2004 till 24 January 2005. This interval is characterized by quiet seismic conditions up to the beginning of November, but rather strong seismic activity occurs in November and December not far from Hokkaido (Japan) and in the region of northern Kuril Islands. There were three series of earthquakes with M=5.6–7.1 in a zone of sensitivity of our wave path during two months. Nighttime "bay-like" phase and amplitude anomalies of the LF signal are observed several days before and during every series of earthquakes. During the whole period of seismic activity a significant shift in terminator times is also evident. The spectrum of LF seismo-induced anomalies shows a clear increase for the period of about 25 min.
Vertical dipoles to detect self potential signals in a seismic area of southern Italy: Tito station
Authors: Colangelo G. , Lapenna V. , Telesca L.
Published: April 2010

Abstract. Since 2000 the Institute of Methodologies for the Environmental Analysis (National Council of Research, Tito, Italy) installed a geophysical monitoring network able to detect geoelectric, geochemic and seismometric parameters in seismic areas of southern Italy. During this period a very large data-base of geophysical time series has been organized and it is actually available to assess robust statistical methodologies to identify geophysical anomalous patterns linked with local seismicity. To better understand the influence of rain and cultural noise on geoelectrical signals (Self Potential), during May 2004 we drilled in Tito station a 20 m-depth hole to measure the SP vertical component. The array is characterized by five Pb-PbCl2 electrodes put at different depths. The common electrode is fixed at 20 m. In this work we present some electrical anomalies probably correlated with local seismic activity on vertical dipoles recorded in Tito station.
Probabilistic seismic hazard map for Romania as a basis for a new building code
Authors: Ardeleanu L. , Leydecker G. , Bonjer K.-P. , Busche H. , Kaiser D. , Schmitt T.
Published: April 2010

Abstract. A seismic hazard map proposed as part of a new building code for Romania is presented here on basis of the recommendations in EUROCODE 8. Seismic source zones within an area of about 200 km around Romania were constructed considering seismicity, neotectonics and geological development. The probabilistic seismic hazard assessment in terms of intensities is performed following Cornell (1968) with the program EQRISK (see Mc Guire, 1976), modified by us for use of intensities. To cope with the irregular isoseismals of the Vrancea intermediate depth earthquakes a factor Ω is introduced to the attenuation law (Kövesligethy, 1907). Using detailed macroseismic maps of three earthquakes Ω is calculated by fitting the attenuation law to observed intensities, i.e. to local ground conditions. Strong local variation of Ω is avoided by a gridding of 0.5° in longitude and 0.25° in latitude. The contribution of the Vrancea intermediate depth zone to the seismic hazard at each grid point is computed with the corresponding representative Ω. A seismogenic depth of 120 km is assumed. The final seismic hazard is the combination of both contributions, of zones with crustal earthquakes and of the Vrancea intermediate depth earthquakes zone. Calculations are done for a recurrence period of 95, 475 and 10000 years. All maps show the dominating effects of the intermediate depth earthquakes in the Vrancea zone, also for the capital Bucharest.
Possible seismogenic origin of changes in the ULF EM resonant structure observed at Teoloyucan geomagnetic station, Mexico, 1999-2001
Authors: Kotsarenko A. , Molchanov O. , Pérez Enríquez R. , López Cruz-Abeyro J. A. , Koshevaya S. , Grimalsky V. , Kremenetsky I.
Published: April 2010

Abstract. The evolution of the ULF resonant structure observed at Teoloyucan geomagnetic station has been provisionally studied in a possible relation with seismic activity in Mexico in the period 1999-2001. Two resonant lines were observed in the H-component (linear polarization) in the frequency bands fR2=10.2–11.1 mHz and fR2=13.6–14.5 mHz, sometimes accompanied by other harmonics. The source of the observed resonances is possibly related with the geomagnetic location of the station (geomagnetic latitude λ=29.1°) and its proximity to the equatorial electrojet (λ~30°). An enhancement of the carrier frequency of both resonances in the period 1 month–2 weeks was found before the strongest EQs. Also, a depression of the resonant structure just a few days before and a few days after some EQs seems to be correlated with seismic activity.
1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea) and their relation to tsunamis
Authors: Altinok Y. , Alpar B. , Özer N. , Gazioglu C.
Published: April 2010

Abstract. The most earthquake-prone areas in the eastern central Aegean Sea are the Izmir Bay, the Karaburun peninsula and the island of Chios. The level of seismic activity and tsunami potential are influenced by the presence of normal faults around the region. There have been about 20 moderate-size earthquakes from 496 BC to 1949 AD. Among these earthquakes, the ones on the dates 20 March 1389, 13 November 1856, 19/22 January 1866, 3 April 1881 and 23 July 1949 produced tsunamis. The Chios-Cesme earthquake (1881, Mw 6.5) took place in the South of the Cesme strait while the Chios-Karaburun earthquake (1949, Mw 6.7) occurred in the North. The tsunamis caused by the earthquakes affected the coasts of Chios Island and Cesme. These waves are thought to be associated with the earthquakes and co-seismic underwater failures possibly occurred along the coasts of the Chios Island and Karaburun Peninsula or on the complex subaqueous morphology between these lands. Some sea waves or oscillations observed following the aftershocks are believed to be related to other natural phenomena; e.g. the seiches occurred mainly in open-narrow bays as triggered by the earthquakes.
A possible preseismic anomaly in the ground wave of a radio broadcasting (216 kHz) during July-August 1998 (Italy)
Authors: Biagi P. F. , Castellana L. , Maggipinto T. , Piccolo R. , Minafra A. , Ermini A. , Martellucci S. , Bellecci C. , Perna G. , Capozzi V. , Molchanov O. A. , Hayakawa M.
Published: April 2010

Abstract. On February 1996, a receiver able to measure the electric field strength of LF radio broadcastings, with a sampling frequency of ten minutes, was put into operation in a site (AS) located in central Italy. One of the broadcasting stations selected is MCO (f=216 kHz), located in southeast France, 518 km far from the receiver. The MCO data collected since February 1996 up to September 2004 were examined and, at first, the night time data and the day time data (in winter and summer) were separated. Then, the wavelet analysis on the night and day time data was applied. The main result of the analysis was the appearance of a very clear anomaly during summer (July–August) 1998, at day time and at night time. The anomaly is a strong exaltation of the signal components with period in the 25–40 days range. Theoretical calculations of electric field strength were made and the only way to justify this anomaly seems to be the occurrence of an increase of the ground wave propagation mode of the radio signal. Such an increase could have been produced by an increase of the ground conductivity and by modifications of some parameter of the troposphere, mainly the refractive index. On 15 August 1998 a seismic sequence started with 17 earthquakes (M=2.2–4.6) on the Reatini mountains, a seismogenic zone located 30 km far from the AS receiver along the path MCO-AS. In this paper, the possibility that the previous radio anomaly can be a precursor of this seismic sequence is proposed.
Acoustic emission and released seismic energy
Authors: Gregori G. P. , Paparo G. , Poscolieri M. , Zanini A.
Published: April 2010

Abstract. Intense crises of crustal stress appear to cross large regions, and to precede by several months the eventual occurrence of some strong earthquake within them. The phenomenon is not linear, and the stress control reflects some wide scale-size rather than local effects. The stress propagation through the crust can be effectively monitored by means of acoustic emission (AE) techniques (ultrasounds). The correlation is here investigated between crustal stress crises and the total release of seismic energy within some space domain around the AE recording site. Some clear inferences can be envisaged, although a significant diagnosis of the state of the crust within a given region ought to request arrays of simultaneously operated AE recorders. Some case histories are described dealing with the Italian peninsula and with the Cephallonia Island.
Historic records and GIS applications for flood risk analysis in the Salento peninsula (southern Italy)
Authors: Forte F. , Pennetta L. , Strobl R. O.
Published: April 2010

Abstract. The occurrence of calamitous meteoric events represents a current problem of the Salento peninsula (Southern Italy). In fact, flash floods, generated by very intense rainfall, occur not only in autumn and winter, but at the end of summer as well. These calamities are amplified by peculiar geological and geomorphological characteristics of Salento and by the pollution of sinkholes. Floodings affect often large areas, especially in the impermeable lowering zones. These events cause warnings and emergency states, involving people as well as socio-economic goods. A methodical investigation based on the historic flood records and an analysis of the geoenvironmental factors have been performed, using a Geographic Information System (GIS) methodology for database processing in order to identify the distribution of areas with different risk degrees. The data, referring to events that occurred from 1968 to 2004, have been collected in a database, the so-called IPHAS (Salento Alluvial PHenomena Inventory), extracted in an easily consultable table. The final goal is the development of a risk map where the areas that are affected by floodings are included between small ridges, the so-called "Serre". More than 50% of the Salento peninsula shows high or very high risk values. The numerous maps that were utilized and generated represent an important basis in order to quantify the flood risk, according to the model using historic records.
The hydro-meteorological chain in Piemonte region, North Western Italy - analysis of the HYDROPTIMET test cases
Authors: Rabuffetti D. , Milelli M.
Published: April 2010

Abstract. The HYDROPTIMET Project, Interreg IIIB EU program, is developed in the framework of the prediction and prevention of natural hazards related to severe hydro-meteorological events and aims to the optimisation of Hydro-Meteorological warning systems by the experimentation of new tools (such as numerical models) to be used operationally for risk assessment. The objects of the research are the mesoscale weather phenomena and the response of watersheds with size ranging from 102 to 103 km2. Non-hydrostatic meteorological models are used to catch such phenomena at a regional level focusing on the Quantitative Precipitation Forecast (QPF). Furthermore hydrological Quantitative Discharge Forecast (QDF) are performed by the simulation of run-off generation and flood propagation in the main rivers of the territory. In this way observed data and QPF are used, in a real-time configuration, for one-way forcing of the hydrological model that works operationally connected to the Piemonte Region Alert System. The main hydro-meteorological events that affected Piemonte Region in the last years are analysed, these are the HYDROPTIMET selected test cases of 14–18 November 2002 and 23–26 November 2002. The results obtained in terms of QPF and QDF offer a basis to evaluate the sensitivity of the whole hydro-meteorological chain to the uncertainties in the numerical simulations. Different configurations of non-hydrostatic meteorological models are also evaluated.
Undersea landslides: extent and significance in the Pacific Ocean, an update
Authors: Lee H. J.
Published: April 2010

Abstract. Submarine landslides are known to occur disproportionately in a limited number of environments including fjords, deltas, canyons, volcanic islands and the open continental slope. An evaluation of the progress that has been made in understanding Pacific Ocean submarine landslides over the last 15years shows that mapping technologies have improved greatly, allowing a better interpretation of landslide features. Some features previously identified as landslides are being reinterpreted by some as sediment waves. Previously underappreciated environments for landslides such as deep-sea trenches are being recognized and lava deltas are being found to be landslide prone. Landslides are also being recognized much more commonly as a potential source of tsunamis. Landslides that have produced tsunamis in the past are being mapped and in some cases modeled. The flow characteristics of turbidity currents produced by landslides in canyon heads have recently been monitored and the source of these failures has been identified using repeated multibeam mapping. Finally, some landslide deposits are being dated as part of assessing risk to coastal cities from landslide-tsunamis.
The long-term development of avalanche risk in settlements considering the temporal variability of damage potential
Authors: Fuchs S. , Keiler M. , Zischg A. , Bründl M.
Published: April 2010

Abstract. Recent studies on the avalanche risk in alpine settlements suggested a strong dependency of the development of risk on variations in damage potential. Based on these findings, analyses on probable maximum losses in avalanche-prone areas of the municipality of Davos (CH) were used as an indicator for the long-term development of values at risk. Even if the results were subject to significant uncertainties, they underlined the dependency of today's risk on the historical development of land-use: Small changes in the lateral extent of endangered areas had a considerable impact on the exposure of values. In a second step, temporal variations in damage potential between 1950 and 2000 were compared in two different study areas representing typical alpine socio-economic development patterns: Davos (CH) and Galtür (A). The resulting trends were found to be similar; the damage potential increased significantly in number and value. Thus, the development of natural risk in settlements can for a major part be attributed to long-term shifts in damage potential.
Locating hidden river courses via geo-technical investigation – application in the city of Granada, Spain
Authors: Hernández del Pozo J. C. , Ocete I. , García R. , Carmona R.
Published: April 2010

Abstract. The diversion of natural river courses and subsequent filling by alluvial deposits or anthropic intervention has been hidden by urban development in the majority of the cities. The research we conducted involved monitoring the evolution of a river course and reconnaissance of the original morphology of the fluvial systems. Our research was applied to the section of the River Beiro that flows through the city of Granada, Spain. The research has been carried out using geo-technical methodology based on reconnaissance via dynamic penetration. This allowed us to determine the different degrees of consolidation and compaction in the areas corresponding with the former course of the river, which are now filled by alluvial deposits. In addition, we have backed up our findings with information provided by historical maps of the city of Granada. The results have identified an area wherein buildings are at risk, as evidenced by the detrimental effects registered in the buildings in this area.
Magnetic and Electromagnetic signals related to tectonic activity: updates and new analyses on measurements in Central Italy
Authors: Di Mauro D. , Lepidi S. , Meloni A. , Palangio P.
Published: April 2010

Abstract. Tectonomagnetic field observations from absolute magnetic field levels have been collected in Central Italy since 1989 by means of a network of four absolute magnetometer stations, including the geomagnetic observatory of L'Aquila (42°23 N, 13°19 E) used as reference for differentiation; also electromagnetic variations from VLF signals have been recorded in the last years by means of VLF search coil wide-band antennas. Many reports proved the occurrence of electromagnetic effects clearly related to tectonic events (seismic and volcanic activity) in active areas of our planet. In this paper we show the variation of some electromagnetic parameters which could be related to local and regional seismic activity for the most recent years 2002 and 2003. We also report the seismic activity recorded in this area by the Italian seismic national network. Some tentative analysis (in the wavelets and statistical approach) on the historical and recent dataset allow a better characterization of electromagnetic properties of the study area, at different temporal and spatial scales.
Radar analysis of the life cycle of Mesoscale Convective Systems during the 10 June 2000 event
Authors: Rigo T. , Llasat M. C.
Published: April 2010

Abstract. The 10 June 2000 event was the largest flash flood event that occurred in the Northeast of Spain in the late 20th century, both as regards its meteorological features and its considerable social impact. This paper focuses on analysis of the structures that produced the heavy rainfalls, especially from the point of view of meteorological radar. Due to the fact that this case is a good example of a Mediterranean flash flood event, a final objective of this paper is to undertake a description of the evolution of the rainfall structure that would be sufficiently clear to be understood at an interdisciplinary forum. Then, it could be useful not only to improve conceptual meteorological models, but also for application in downscaling models. The main precipitation structure was a Mesoscale Convective System (MCS) that crossed the region and that developed as a consequence of the merging of two previous squall lines. The paper analyses the main meteorological features that led to the development and triggering of the heavy rainfalls, with special emphasis on the features of this MCS, its life cycle and its dynamic features. To this end, 2-D and 3-D algorithms were applied to the imagery recorded over the complete life cycle of the structures, which lasted approximately 18 h. Mesoscale and synoptic information were also considered. Results show that it was an NS-MCS, quasi-stationary during its stage of maturity as a consequence of the formation of a convective train, the different displacement directions of the 2-D structures and the 3-D structures, including the propagation of new cells, and the slow movement of the convergence line associated with the Mediterranean mesoscale low.