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Induced seismicity as generated by the injection of fluids in a homogeneous, permeable medium with faults with variable proximity to rupture conditions is simulated using the rate- and state-dependent frictional fault theory (RST) of Dieterich (J Geophys Res 99(B2):2601–2618, 1994) and the critical pressure theory (CPT) developed by Shapiro (Fluid-induced seismicity, Cambridge University Press, Cambridge, 2015). In CPT, the induced local seismicity density is proportional to the pressure rate, limited by the Kaiser Effect, and apparently un-related to the tectonic background seismicity. There is no time delay between a change in pressure rate and seismicity density. As a more complex theory, RST includes a time delay between a pressure change and induced seismicity and it is proportional to the natural tectonic background seismicity. Comparing both modelling approaches at a fixed location, this delay can be significant, dependent on a ‘free’ parameter that represents the lower threshold for pressure below which seismicity is not triggered. This parameter can be tuned so that the results of CPT and RST become similar. Approximations of the RST allow a new interpretation of the parameter ‘tectonic potential’ that controls the level of induced seismicity in CPT.

We estimate damage and loss to the residential building stock from tephra fallout for a re-eruption of the Laacher See Volcano in Germany with similar volcanological features as compared to the 10900BCE eruption (VEI = 6) but current population and wind conditions. This eruption was the largest eruption north of the Alps since the Late Quaternary. It generated several fallout fans with proximal deposits of several meters in height. The main cities that would be affected today are Cologne, Bonn, Koblenz and Frankfurt with a total population of at least 2.2 million people. We derive possible wind fields from an analysis of 44years of radiosonde observations provided by the Deutsche Wetterdienst (DWD). As they vary significantly with season, the loss numbers and patterns reflect this dependency. We use the HAZMAP software to calculate the spatial distribution of tephra. HAZMAP simulates the tephra distribution using a 2D advection-diffusion-sedimentation model. The tephra load as a hazard parameter is used to quantify roof and building damage. As the physical parameter for damage due to snow loads is comparable, we utilise the available knowledge on snow load damage to buildings and derive vulnerability curves that are representative within a geo-cell of 500 × 500m. Available information on the replacement values in each geo-cell are derived and loss estimation is undertaken. Depending on the wind conditions, we calculate a range of 18 to 27 billion Euros for the various scenarios. These absolute numbers translate to Mean Damage Ratios (MDR, ratio of absolute loss to Capital Stock in the affected area) of about 4%. This is very close to the MDR of the 1991 VEI 6 Pinatubo eruption in the Philippines.

On 22 January 2013 an earthquake with local magnitude ML 4.1 occurred in the central part of the Gulf of Suez. Six months later on 1 June 2013 another earthquake with local magnitude ML 5.1 took place at the same epicenter and different depths. These two perceptible events were recorded and localized by the Egyptian National Seismological Network (ENSN) and additional networks in the region. The purpose of this study is to determine focal mechanisms and source parameters of both earthquakes to analyze their tectonic relation. We determine the focal mechanisms by applying moment tensor inversion and first motion analysis of P- and S-waves. Both sources reveal oblique focal mechanisms with normal faulting and strike-slip components on differently oriented faults. The source mechanism of the larger event on 1 June in combination with the location of aftershock sequence indicates a left-lateral slip on N-S striking fault structure in 21 km depth that is in conformity with the NE-SW extensional Shmin (orientation of minimum horizontal compressional stress) and the local fault pattern. On the other hand, the smaller earthquake on 22 January with a shallower hypocenter in 16 km depth seems to have happened on a NE-SW striking fault plane sub-parallel to Shmin. Thus, here an energy release on a transfer fault connecting dominant rift-parallel structures might have resulted in a stress transfer, triggering the later ML 5.1 earthquake. Following Brune’s model and using displacement spectra, we calculate the dynamic source parameters for the two events. The estimated source parameters for the 22 January 2013 and 1 June 2013 earthquakes are fault length (470 and 830 m), stress drop (1.40 and 2.13 MPa), and seismic moment (5.47E+21 and 6.30E+22 dyn cm) corresponding to moment magnitudes of MW 3.8 and 4.6, respectively.

We focused on validation of applicability of semi-empirical technique (spectral models and stochastic simulation) for the estimation of ground-motion characteristics in the northeastern region (NER) of India. In the present study, it is assumed that the point source approximation in far field is valid. The one-dimensional stochastic point source seismological model of Boore (1983) (Boore, DM. 1983. Stochastic simulation of high frequency ground motions based on seismological models of the radiated spectra. Bulletin of Seismological Society of America, 73, 1865–1894.) is used for modelling the acceleration time histories. Total ground-motion records of 30 earthquakes of magnitudes lying between MW 4.2 and 6.2 in NER India from March 2008 to April 2013 are used for this study. We considered peak ground acceleration (PGA) and pseudospectral acceleration (response spectrum amplitudes) with 5% damping ratio at three fundamental natural periods, namely: 0.3, 1.0, and 3.0 s. The spectral models, which work well for PGA, overestimate the pseudospectral acceleration. It seems that there is a strong influence of local site amplification and crustal attenuation (kappa), which control spectral amplitudes at different frequencies. The results would allow analysing regional peculiarities of ground-motion excitation and propagation and updating seismic hazard assessment, both the probabilistic and deterministic approaches.

A theoretical frame of seismicity evolution due to stress changes in a medium is the rate- and state-dependent theory of frictional fault motion. The evolution is expressed in the form of a differential equation, which can be used for normal stress changes on faults caused by fluid pressure changes resulting from injection. If the pressures rate is high enough the seismic activity becomes proportional to the local pressure rate in accordance with the Critical Pessure Theory. Examples including constant pressure injection, shut-in and variable injection rates lead to results comparable to the Critical Pressure Theory.

We analysed the within-earthquake correlation of ground motion using the strong-motion records accumulated by the TSMIP (Taiwan Strong Motion Instrumentation Program) network in Taiwan during 1993–2009. Two ground-motion prediction equations, which were recently developed for peak ground acceleration (PGA) in the region and based on moment and local magnitude and hypocentral distance, were used for the calculation and analysis of ground-motion residuals. We also used the database containing shear-wave velocity data averaged for the top 30 m of the soil column (Vs30) for the TSMIP stations. We showed that the within-earthquake correlation may vary significantly depending on site classes, gross geological features of the area, and magnitude of earthquakes, records of which dominate the analysed dataset. On the one hand, there is a prominent correspondence between the within-earthquake correlation of PGA residuals and spatial correlation of Vs30 values, which was estimated for particular geological structures (e.g., sedimentary filled basins and large plain areas). On the other hand, the high level of ground-motion correlation (or significant non-random component of residuals) may be caused by the joint influence of soft surface soil and thick sediments and by the path or azimuthal effects. The point-source approximation of extended fault and neglected hanging- and foot-wall effects may also result in non-random residuals. The application of empirical correction factors, which consider the magnitude of earthquakes, source-to-site distance and Vs30 value for given stations, allows for the effective reduction in the level of within-earthquake correlation, as well as the within-earthquake standard deviation. The results of the analysis may be used in practical estimates of seismic hazard, damage and loss for spatially distributed structures (portfolios, lifelines) in Taiwan, as well in other regions with similar geological characteristics.

The global CATDAT damaging earthquakes and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture) database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic earthquakes. Lack of consistency and errors in other earthquake loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon. Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging earthquakes historically, with over 7000 earthquakes since 1900 examined and validated before insertion into the database. Each validated earthquake includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected), and economic losses (direct, indirect, aid, and insured). Globally, a slightly increasing trend in economic damage due to earthquakes is not consistent with the greatly increasing exposure. The 1923 Great Kanto ($214 billion USD damage; 2011 HNDECI-adjusted dollars) compared to the 2011 Tohoku (>$300 billion USD at time of writing), 2008 Sichuan and 1995 Kobe earthquakes show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product), exchange rate, wage information, population, HDI (Human Development Index), and insurance information have been collected globally to form comparisons. This catalogue is the largest known cross-checked global historic damaging earthquake database and should have far-reaching consequences for earthquake loss estimation, socio-economic analysis, and the global reinsurance field.

The importance of critical infrastructures and strategic planning in the context of extreme events, climate change and urbanization has been underscored recently in international policy frameworks, such as the Sustainable Development Goals (SDGs), the Sendai Framework for Disaster Risk Reduction 2015–2030 (UNISDR (United Nations/International Strategy for Disaster Risk Reduction) 2015), and the new Paris climate agreement (UNFCCC (United Nations — Framework Convention on Climate Change) 2015) as well as the New Urban Agenda (UN-HABITAT 2016). This paper outlines key research challenges in addressing the nexus between extreme weather events, critical infrastructure resilience, human vulnerability and strategic planning. Using a structured expert dialogue approach (particularly based on a roundtable discussion funded by the German National Science Foundation (DFG)), the paper outlines emerging research issues in the context of extreme events, critical infrastructures, human vulnerability and strategic planning, providing perspectives for inter- and transdisciplinary research on this important nexus. The main contribution of the paper is a compilation of identified research gaps and needs from an interdisciplinary perspective including the lack of integration across subjects and mismatches between different concepts and schools of thought.

The August 17, 1999 Kocaeli earthquake ruptured the earth’s surface along 145 km and produced a magnitude of M w =7.4. As expected for such an event Modified Mercalli intensities of typically IX and X in the vicinity of the fault were determined. Yet the observed accelerations at the five near-fault sites remained amazingly small with horizontal PGA values of 0.14 g to 0.4 g. We attempt to resolve the enigma by modeling surface ground motion with a finite-difference algorithm, utilizing two different rupture and slip histories derived from the strong-motion observations and ‘translate’ the computed horizontal motion in intensity values. We can show that (a) in a given simple crustal velocity model different slip distributions result in significantly different ground motion distributions in the vicinity of the fault even though both slip distributions fit the observed accelerometer data quite well. (b) Both slip distributions ‘project’ high ground motion into areas adjacent to the fault where no accelerometer was located. (c) Both slip distributions are not fully compatible with observed intensity observations around the fault, although this could be partly attributed to the lack of knowledge regarding to the crustal structure. In the light of our results it would thus be misleading if the few strong-motion observations around the Kocaeli earthquake fault were taken as typical or representative for the entire area and for potential future events.

The northern Upper Rhine Graben, situated in the central part of the European Cenozoic rift system, is currently characterized by low intra-plate seismicity. Historical earthquakes have not been large enough to produce surface rupturing. Moreover, the records of Quaternary surface processes and human modifications are presumably better preserved than the record of the relatively slow tectonic deformation. In order to gain information on the neotectonic activity and paleoseismicity in this setting, the geological and geomorphological records of fault movements along a segment of the Western Border Fault (WBF) were studied using an integration of techniques in paleoseismology, structural analysis and shallow geophysics. The WBF segment investigated follows a 20 km long linear scarp of unclear origin. A series of geophysical measurements were performed and the results suggested that near-surface deformation structures are present at the segments' southern end. Several trenches opened at this location revealed fault structures with consistent extensional style and a maximum vertical displacement of 0.5 m. In one trench, the deformation structures were dated between 19 and 8 ka. Assuming the deformation has been caused by an earthquake, a Mw ∼6.5 earthquake would be implied. Aseismic deformation would point to a fault creep rate ≥ 0.04 mm/yr. A reconstruction of the sequence of events at the trench site, from Middle Pleistocene to Present, demonstrates that the morphology at the base of the scarp is the result of interplay between tectonic activity and fluvial and erosional processes. At the regional scale, a mixed origin for the WBF scarp is proposed, combining the effects of fluvial dynamics, erosion, regional uplift and localized tectonic activity on the WBF.

In the past few decades, devastating earthquakes have caused high social and economic losses in cities. Earthquakes cannot be avoided, but the devastating impacts, especially fatalities, can be minimized through pre-event emergency response planning and preparedness. The development of emergency plans strongly relies on up-to-date population and inventory data. However, existing techniques for population data generation do not meet the requirements of many of today’s dynamic cities. In this context, the importance of remote sensing as a cutting-edge technology for data acquisition in urban areas is increasing. The present study analyzes the capacities and limitations of high resolution optical satellite imagery (IKONOS) for modeling population distribution in the district of Zeytinburnu in Istanbul, Turkey. The results show remote sensing to be an independent, up-to-date and area-wide data source. The use of remote sensing facilitates a mechanism to provide necessary quantitative information on urban morphology and population distribution in a fast and accurate way. The generated data do not have the quality of cadastral data sets but they meet the requirements of identifying bottlenecks, highly risky zones, etc. and can serve as a base for decision making.

The 4-D evolution of topography is a complex scientific topic in geosciences that requires interdisciplinary efforts. In Europe, increased attention toward this research topic was originally coordinated by the TOPO-EUROPE initiative (Cloetingh et al. 2007), which has led to a continent-wide research program under the auspices of the European Science Foundation. One project within that framework is titled “TopoScandiaDeep— the Scandinavian Mountains: Deep Processes,” which aims at developing a self-consistent geophysical model for the lithosphere-asthenosphere system under southern Norway and at understanding the mechanisms that led to mountain-building far away from the plate boundary. A major component of the project is the analysis of recently acquired, passive seismological data from the MAGNUS ( MA ntle investi G ations of N orwegian U plift S tructures) experiment. The temporary network covered the high topography of southern Norway, which is, in the absence of compressional tectonics, a typical example of a particular geoscientific problem that is still not entirely understood—the origin of high topography along passive continental margins ( e.g. , Japsen and Chalmers 2000). Along the Northeast-Atlantic continental margin, at the western rim of the Fennoscandian shield, this topography is expressed through the Scandes mountain range, the second largest mountain range in Europe (Figure 1). It extends over a total length of more than 2,000 km along the entire Norwegian coast and has a peak topography of up to 2,500 m. With a few exceptions, such as the alpine formation in Sunnmore (central Norway), the topography is rather smooth, to a large extent dominated by subplanar (paleic) surfaces at elevations above 500 m. Contrary to the central European Alps, whose orogeny is in principle well understood as a classic collision belt, the evolution of the Scandes and its high topography remains an unsolved and highly debated issue. In particular the vicinity of …

The May 2006 Central Java earthquake (M w =6,3) heavily struck the Special Province of Yogyakarta, Indonesia. The widespread damage and high number of casualties revealed the necessity of vulnerability assessment within this region. A vulnerability and risk analysis was conducted using a GIS-based Indicator-Index Method. In this analysis very high resolution satellite images were used for two purposes: Firstly to validate the risk map by detecting damaged areas. This lead to the development of an object-based and a pixel-based methodology for damage detection. The detected damage areas were analyzed on a building unit scale. For each building unit the damage was calculated. Secondly to extract detailed information on the spatial distribution of landuse in the study area. This was conducted using a object-based, multiresolution approach.

Nowadays natural disasters phenomena as hurricanes, volcanic eruptions, tsunamis or earthquakes, are still difficult to prevent. Based on signaling of the phenomenon appearance in the destructive area, important human losses and material damages are avoided. For that reason, WARNING turns into a key objective, both in theoretical and practical research.

TOPO-EUROPE addresses the 4-D topographic evolution of the orogens and intra-plate regions of Europe through a multidisciplinary approach linking geology, geophysics, geodesy and geotechnology. TOPO-EUROPE integrates monitoring, imaging, reconstruction and modelling of the interplay between processes controlling continental topography and related natural hazards. Until now, research on neotectonics and related topography development of orogens and intra-plate regions has received little attention. TOPO-EUROPE initiates a number of novel studies on the quantification of rates of vertical motions, related tectonically controlled river evolution and land subsidence in carefully selected natural laboratories in Europe. From orogen through platform to continental margin, these natural laboratories include the Alps/Carpathians-Pannonian Basin System, the West and Central European Platform, the Apennines-Aegean-Anatolian region, the Iberian Peninsula, the Scandinavian Continental Margin, the East-European Platform, and the Caucasus-Levant area. TOPO-EUROPE integrates European research facilities and know-how essential to advance the understanding of the role of topography in Environmental Earth System Dynamics. The principal objective of the network is twofold. Namely, to integrate national research programs into a common European network and, furthermore, to integrate activities among TOPO-EUROPE institutes and participants. Key objectives are to provide an interdisciplinary forum to share knowledge and information in the field of the neotectonic and topographic evolution of Europe, to promote and encourage multidisciplinary research on a truly European scale, to increase mobility of scientists and to train young scientists. This paper provides an overview of the state-of-the-art of continental topography research, and of the challenges to TOPO-EUROPE researchers in the targeted natural laboratories. © 2007 Elsevier B.V. All rights reserved.

Global earthquake statistics shows that in the long-term average, each year the globe is hit by one event in excess of (moment) magnitude 8.0 and by 18 events in excess of magnitude 7.0. Clearly if these events strike in the vicinity of an urbanised area high damage and high mortality and casualty rates can be expected. For instance on July 28, 1976 at 3:42 a.m. local time an earthquake with a (moment) magnitude of 7.5 occurred beneath the Chinese city of Tangshan, located about 200 km to the East of Beijing. Of the city’s one million inhabitants 240,000 were killed and 760,000 injured. The city experienced an intensity of X (out of XII) and was almost completely destroyed with 100% residential buildings and 80% commercial buildings collapsed [1]. Until 1976 the hazard, to which the city was exposed, had been completely underestimated by assuming that it would not have to face more than intensity VI. Tangshan stands as an example of what can happen to a vulnerable large city in the developing world: complete destruction, and more than 20% of inhabitants dead.

Early Warning Systems (EWS) have the potential to warn the population, government officials, police, fire department, and operators of vital and/or hazardous facilities. The options available for response within the warning time depends very much on its length. For instance, the EWS of Mexico City provides 60 to 75 seconds of advance warning. This represents the time delay between strong motion recorded at the subduction zone where the Cocos plate slides beneath North America and felt in the city 300 to 350 km away.