440 research outputs found
Scenario-based earthquake hazard and risk assessment for Baku (Azerbaijan)
A rapid growth of population, intensive civil and industrial building, land and water instabilities (e.g. landslides, significant underground water level fluctuations), and the lack of public awareness regarding seismic hazard contribute to the increase of vulnerability of Baku (the capital city of the Republic of Azerbaijan) to earthquakes. In this study, we assess an earthquake risk in the city determined as a convolution of seismic hazard (in terms of the surface peak ground acceleration, PGA), vulnerability (due to building construction fragility, population features, the gross domestic product per capita, and landslide's occurrence), and exposure of infrastructure and critical facilities. The earthquake risk assessment provides useful information to identify the factors influencing the risk. A deterministic seismic hazard for Baku is analysed for four earthquake scenarios: near, far, local, and extreme events. The seismic hazard models demonstrate the level of ground shaking in the city: PGA high values are predicted in the southern coastal and north-eastern parts of the city and in some parts of the downtown. The PGA attains its maximal values for the local and extreme earthquake scenarios. We show that the quality of buildings and the probability of their damage, the distribution of urban population, exposure, and the pattern of peak ground acceleration contribute to the seismic risk, meanwhile the vulnerability factors play a more prominent role for all earthquake scenarios. Our results can allow elaborating strategic countermeasure plans for the earthquake risk mitigation in the Baku city
Geoscience international : the role of scientific unions
International geoscientific unions (geounions) have been coordinating and promoting international efforts in Earth and space sciences since the beginning of the 20th century. Thousands of scientists from many nations and specific scientific disciplines have developed ways of cooperation through international unions and learned how to work together to promote basic geosciences. The unions have been initiating, developing, and implementing international cooperative programmes, setting scientific standards, developing research tools, educating and building capacity, and contributing to science for policy. This paper analyses the role of geounions in and their added value to the promotion of geoscience internationally in the arena of the existing and emerging professional societies of geoscientists. The history of the geounions and the development of international cooperation in geosciences are reviewed in the paper in the context of scientific and political changes over the last century. History is considered here to be a key element in understanding and shaping the future of geounions. Scientific and organisational aspects of their activities, including cooperation with international and intergovernmental institutions, are analysed using the example of the International Union of Geodesy and Geophysics (IUGG). The geounions’ activities are compared to those of professional societies. Future development of scientific unions and their role in the changing global landscape of geosciences are discussed
Natural hazards and climate change are not drivers of disasters
Many nations face challenges in assessing, understanding, and responding to the time-dependent nature of disaster risk. Changes in the intensity of occurrences of extreme events coupled with changes in vulnerability and exposure alter the impacts of natural hazards on society in mostly negative ways. Here an interrelationship between natural hazard (NH), climate change (CC), vulnerability (V), exposure (E), and decisionmaking (DM) is considered. While NHs trigger disasters and CC is likely to intensify occurrences of disasters, V and E present major drivers of disasters. Informed DM on disaster risk reduction should be based on scientific evidence from NH and CC, knowledge of V and E, and relevant options for actions on preventive disaster measures as a part of preparedness and public awareness
Numerical Modelling of Lithospheric Block-and-Fault Dynamics: What Did We Learn About Large Earthquake Occurrences and Their Frequency?
Feasibility of the Sudden (Daf'ī) Revelation of the Entire Qur'an on Laylat al-Qadr and Determinism Doubt
One of the important issues of the Qur’anic sciences is the quality of the Qur'an's revelation, which scholars consider to be two types including sudden and gradual. In spite of the sudden revelation of the Qur'an on the heart of the Prophet, it is suspected that all the events during the 23 years of the Prophet's lifetime have been deterministic, the events such as: emigration, wars and other matters mentioned in the narratives of the Asbab al-Nuzūl; therefore, the sudden revelation is unacceptable. So, in this descriptive-analytic study, this question has been answered and the incompatibility of the sudden revelation of the Holy Qur’an on Laylat al-Qadr was proved by the issue of human will with different arguments. Through this research, it was proved that the sudden revelation is a part of knowledge and, first, that knowledge is not the cause of occurrence until determinism is suspected. Secondly, the knowledge of God over the acts of servants is not absolute, but the knowledge of God has been belonged to the authoritative subject issued by the authoritative subject and the compulsory subject issued by the compulsory subject. Therefore, the sudden revelation of the Qur'an, which charts future events and issues, demands that the act of authoritative subject be issued by an authoritative subject and that the act of compulsory subject be issued by a compulsory subject, rather than requiring the authoritative subject be forced or a compulsory subject be authorized. In addition, determinism contradicts the spirit of the teachings of the Qur'an which imply responsibility and duty
Preface to the special issue “The International Union of Geodesy and Geophysics: from different spheres to a common globe”
Seismic hazard assessment of the Shillong Plateau using a probabilistic approach
Seismotectonic processes of the Shillong Plateau (SP) have been influenced by the Himalayan orogeny, the India-Burmese subduction, and the Bengal Basin evolution leading to high seismic activity in the region. With a goal of assessing seismic hazards in the SP and providing a scientific information to engineering and disaster risk management communities, a probabilistic seismic hazard analysis is employed to determine hazard in highly-populated districts of SP and particularly in Shillong, Nongpoh, and Tura cities, located within the districts. This analysis is based on the use of historical and instrumentally recorded regional earthquakes since 1411 and deals with uncertainties related to earthquake magnitudes, rupture locations, and the frequency of ground motion exceedance. Individual hazard curves indicate that the Barapani fault possesses the highest frequency of seismic hazard for Shillong city and Nongpoh, and the Eocene hinge zone and Dauki faults are responsible for the highest frequency of seismic hazard at Tura. The results of the hazard assessment together with those obtained earlier using a scenario-based approach demonstrate that although the Oldham fault located near Tura can produce a great, but rare earthquake, few other nearby faults are capable of producing smaller magnitude events with a higher probability of occurrence
Linking mantle upwelling with the lithosphere descent and the Japan Sea evolution: a hypothesis
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