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Central Asian countries, which include Kazakhstan, the Kyrgyz Republic, Tajikistan, Turkmenistan, and Uzbekistan, are known to be highly exposed to natural hazards, particularly earthquakes, floods, and landslides. With the aim of enhancing financial resilience and risk-based investment, planning to promote disaster and climate resilience in Central Asia, the European Union, in collaboration with the World Bank and the Global Facility for Disaster Reduction and Recovery (GFDRR), launched the Strengthening Financial Resilience and Accelerating Risk Reduction in Central Asia (SFRARR) regional programme. Within this framework, a consortium of national and international scientific institutions was established and tasked with developing a regionally consistent multi-hazard and multi-asset probabilistic risk assessment. The overall goal was to improve scientific understanding on local perils and to provide local stakeholders and governments with up-to-date tools to support risk management strategies. However, the development of a comprehensive risk model can only be done with the basis of an accurate hazard evaluation, the reliability of which depends significantly on the availability of local data and direct observations. This paper describes the preparation of the input datasets required for the implementation of a probabilistic earthquake model for the Central Asian countries. In particular, it discusses the preparation of a new regional earthquake catalogue harmonized between countries and homogenized in moment magnitude (Mw), as well as the preparation of a regional database of selected active faults with associated slip rate information to be used for the construction of the earthquake source model. The work was carried out in collaboration with experts from the local scientific community, whose contribution proved essential for the rational compilation of the two harmonized datasets.

Abstract We investigated the spatial relationships among 18 known seismogenic faults and 1651 wells drilled for gas exploitation in the main hydrocarbon province of northern-central Italy, a unique dataset worldwide. We adopted a GIS approach and a robust statistical technique, and found a significant anticorrelation between the location of productive wells and of the considered seismogenic faults, which are often overlain or encircled by unproductive wells. Our observations suggest that (a) earthquake ruptures encompassing much of the upper crust may cause gas to be lost to the atmosphere over geological time, and that (b) reservoirs underlain by smaller or aseismic faults are more likely to be intact. These findings, which are of inherently global relevance, have crucial implications for future hydrocarbon exploitation, for assessing the seismic–aseismic behaviour of large reverse faults, and for the public acceptance of underground energy and CO2 storage facilities—a pillar of future low carbon energy systems—in tectonically active areas.

The integrated analysis using different seismic wave types in a record is a very efficient approach for a comprehensive characterization of marine sediments, especially in shallow water conditions. The proposed integrated method to analyze seismic data in post-critical conditions consists of: 1) the inversion of Scholte waves to obtain a reliable Vs distribution of the near seafloor; 2) pre-processing of seismic data; 3) construction of the P-wave velocity field by using all available information, including available well data; and 4) the application of the wave equation datuming and post-processing, such as pre-stack time migration. We demonstrate how this approach could be successfully applied on seismic datasets characterized by post-critical conditions and the occurrence of the Scholte waves, which may be exploited to provide fundamental information instead of being only an unwanted effect. The integrated analysis of seismic events can thus help, together with data processing, by providing better seismic imaging, which is a priority for a reliable seismostratigraphic interpretation.

The paper presents a methodology for the multi-hazard fragility analysis of fluvial earthen dikes in earthquake- and flood-prone areas due to liquefaction. The methodology has been applied for the area along the Rhine River reach and adjacent floodplains between the gauges at Andernach and Düsseldorf. Along this domain, the urban areas are partly protected by dikes, which may be prone to failure during exceptional floods and/or earthquakes. The fragility of the earthen dikes is analysed in terms of liquefaction potential, characterized by the factor of safety estimated using the procedure of Seed and Idriss (1971). Uncertainties in the geometrical and geotechnical dike parameters are considered in a Monte Carlo simulation (MCS). Failure probability of the earthen structures is presented in the form of a fragility surface as a function of both seismic hazard and hydrologic/hydraulic load.

Both aleatory and epistemic uncertainties associated with different sources and components of risk (hazard, exposure, vulnerability) are present at each step of seismic risk assessments. All individual sources of uncertainty contribute to the total uncertainty, which might be very high and, within the decision-making context, may therefore lead to either very conservative and expensive decisions or the perception of considerable risk. When anatomizing the structure of the total uncertainty, it is therefore important to propagate the different individual uncertainties through the computational chain and to quantify their contribution to the total value of risk. The present study analyses different uncertainties associated with the hazard, vulnerability and loss components by the use of logic trees. The emphasis is on the analysis of epistemic uncertainties, which represent the reducible part of the total uncertainty, including a sensitivity analysis of the resulting seismic risk assessments with regard to the different uncertainty sources. This investigation, being a part of the EU FP7 project MATRIX (New Multi-Hazard and Multi-Risk Assessment Methods for Europe), is carried out for the example of, and with reference to, the conditions of the city of Cologne, Germany, which is one of the MATRIX test cases. At the same time, this particular study does not aim to revise nor to refine the hazard and risk level for Cologne; it is rather to show how large are the existing uncertainties and how they can influence seismic risk estimates, especially in less well-studied areas, if hazard and risk models adapted from other regions are used.

p-Tetrakis(phenylazo)-tetra-hydroxythiacalix[4]arene shows complexing properties with neutral molecules. A complex with pyridine was crystallized and the crystal structure determined. The crystals are monoclinic, space group C2/c, a = 49.953(10), b = 21.566(4), c = 23.448(5) Å, β = 105.12(3)°, V = 24386(8) Å 3, Z = 16. Two macrocycles are positioned in such a way that they form a cavity where two pyridine molecules are encapsulated giving a 2:2 endocomplex. 5.5 other pyridine molecules are trapped between the macrocycles, two of them giving H-bonds with the calixarenes. [ABSTRACT FROM AUTHOR]

An inversion of Pn arrival times from regional distance earthquakes (180-800 km), recorded by 94 seismic stations operating in North-Western Italy and surrounding areas, was carried out to image lateral variations of P-wave velocity at the crust-mantle boundary, and to estimate the static delay time at each station. The reliability of the obtained results was assessed using both synthetic tests and the bootstrap Monte Carlo resampling technique. Numerical simulations demonstrated the existence of a trade-off between cell velocities and estimated station delay times along the edge of the model. Bootstrap inversions were carried out to determine the standard deviation of velocities and time terms. Low Pn velocity anomalies are detected beneath the outer side of the Alps (-6%) and the Western Po plain (-4%) in correspondence with two regions of strong crustal thickening and negative Bouguer anomaly. In contrast, high Pn velocities are imaged beneath the inner side of the Alps (+4%) indicating the presence of high velocity and density lower crust-upper mantle. The Ligurian sea shows high Pn velocities close to the Ligurian coastlines (+3%) and low Pn velocities (-1.5%) in the middle of the basin in agreement with the upper mantle velocity structure revealed by seismic refraction profiles.

Time-resolved photoluminescence (TRPL) was investigated on passivated silicon wafers under modulated square-wave laser illumination. It is shown that time-correlated single-photon counting can be used to record the transient signals on silicon wafers with doping levels commonly used for photovoltaic applications. This article reports the self calibrated evaluation of the injection-dependent effective minority carrier lifetime from the TRPL measurements. The method only requires knowing the doping level, the incident laser power, the reflection coefficient and the sample thickness. TRPL results were found to be in good agreement with photoconductance lifetime measurements. The effect of the surface recombination velocity on the generation of the PL signal was shown experimentally and discussed with PC1D calculations. [ABSTRACT FROM AUTHOR]