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A catalogue of fault plane solutions for earthquakes recorded in Romania between 1929 and 2012 is analyzed in order to outline statistical features of the fault plane solutions in correlation with the earthquake-prone areas in Romania. The catalogue contains both groups: crustal earthquakes (h < 50 km) and intermediate-depth earthquakes (h > 50 km), but only the crustal earthquakes are analyzed here. The catalogue covers mostly the area in front of the Carpathians Arc: Moesian Platform, Barlad Depression, North Dobrogean Orogen and Fagaras – Câmpulung, Central Southern Carpathian seismogenic zones. The Intra-Carpathians area has a sparse seismicity and the available fault plane solutions are not enough to derive regional horizontal crustal stress based on multiple mechanism solutions. In our present investigations we have employed the formal stress inversions of a group of focal mechanisms (FMF), which is a better estimation of the tectonic stress orientation that can be achieved in a region with a homogeneous regional stress field, in comparison with single focal mechanism, as shown in World Stress Map Project [1]. The formal stress inversion of multiple focal mechanisms (FMF) improves the quality of stress derivation, but it is linked to two main assumptions: (1) the chosen FMS lies in a region with a uniform stress field that is invariant in space and time; (2) the direction of earthquake slip follows the direction of the maximum shear stress, as in Wallace-Bott hypothesis [2]. The 2D horizontal stress is determined in the crustal zones using local grids with cells containing at least 15- 20 fault plane solutions and is graphically represented, using STRESSINVERSE computer programs with public access [3]. [ABSTRACT FROM AUTHOR]

The purpose of this research is to analyze the data recorded on instrumented structures in Bucharest and adjacent free-field seismic stations during the last moderate earthquake that occurred on 28th of October 2018 in the Vrancea seismic zone. The earthquake had a 5.5 moment-magnitude, a depth of 147.8 km, and it was felt on a large area of Romania, generating very little damage in Bucharest. In the last five years, the National Institute for Earth Physics has deployed permanent instrumentation (accelerometers) at key stories of five buildings in Bucharest metropolitan area that recorded the seismic motion of the mentioned earthquake. Three of the buildings have been equipped with seismic isolators and dampers and the performance of this earthquake-protection system was assessed based on earthquake data. The data recorded by four free-field seismic stations located in Bucharest were used as reference motion. In order to assess the amplification or reduction of the seismic waves when propagating in the structure, acceleration and velocity data were analyzed, both in time domain and in frequency domain, for selected frequency ranges. The paper presents also the acquisition setup, the dataflow and the data-processing methods. This study highlights the amplification / reduction of the seismic signal recorded at the ground level by the building structure. In the framework of previous studies on data recorded on buildings located in Bucharest, this study adds new valuable information and contribute to a better understanding of seismic response of buildings. [ABSTRACT FROM AUTHOR]

Research institutions and academia play an important role in developing new methods for disaster management and advancing the state-of-the art in risk reduction. In the case of natural disaster studies, fundamental research and theoretical approaches can be directed towards the development of new tools and technologies with direct applicability in the management of emergency situations and in risk mitigation. What needs to be considered by all those actors who can contribute to strengthening the response capacity and raising the level of information of decision-makers, intervention units and society is precisely the adjustment of the tools developed for the purpose in which they will be used. The information required by decision makers covers a wide range of spatial and temporal scales and more important, needs to be timely delivered, continuously updated, easily accessible and understandable. This becomes a challenge in itself, considering that the information will come at the end of the processing flow and at different stages of scientific analysis and interpretation. In this paper we underline the best practices implemented in Romania, a country with a high seismic risk, through a scientific investigation focused on results of seismic monitoring hazard assessment and active collaboration among institutions involved in natural hazards risk management. Going from GIS mapping tools to early warning system and then to dedicated communication, training and education facilities, the support instruments are discussed in terms of advantages and limitations. We also address the importance of communication among scientists, disaster managers and community planners as well as public outreach to assure that everybody knows what tools available and what issues can be addressed. [ABSTRACT FROM AUTHOR]

Romania is one of the most seismic-prone countries in Europe due to the periodically occurrence of strong intermediate-depth earthquakes in Vrancea seismogenic zone. In the last decades, many efforts were done to gather macroseismic intensities in case of felt Vrancea earthquakes and additionally an online environment was developed for the automatic approximation of the intensity from people feedback. Besides the extended scientific studies, the near real time estimation of the macroseismic intensity recently became mandatory for the insurance companies to cover some of the losses and damage that earthquakes might cause to houses, belongings, and other buildings. The procedure proposed in this paper for rapid macroseismic estimation and loss assessment for the recent intermediate-depth Vrancea earthquakes with MW>4.5 is using the online macroseismic questionnaires, and the automatic intensity estimation code recently improved. Besides the automatic estimation, we have also used the classical approach to assess the intensity data points and also the available equations for conversion of peak ground acceleration in macroseismic intensity (including de Romanian Macroseismic Intensity Standard). [ABSTRACT FROM AUTHOR]

Over the last few years, science has advanced unprecedentedly in explaining phenomena and facts with a high impact on society: earthquakes for example. On the other hand, new technologies are transforming the way (seismological) information is collected and transmitted to public and other various stakeholders categories. From interactive multimedia content to immersive experiences, difficult concepts become easier to be transmitted and understood by a wide variety of audience, starting with children, a most important part of tomorrow's society. But what if the aiming is far more than captivating young people or promoting science and scientific results? How can we, scientists, deliver information in such a way that awareness and mitigation comes immediately after or even together with learning and understanding? For a quake-prone country, earthquakes have to be a major and continuous concern, but depending on the recurrence period of damaging events, effective measures for mitigation might not be disregarded but considered as top priority. Romania is a good example, with an average of 2-3 earthquakes with magnitude greater than 7 per century. Although the seismic hazard was recently reevaluated and ranked one in the top of hazards with the greatest impact on population and economy, and also giving that questionnaires indicated that people are most afraid of earthquakes, the preparedness actions are very slow in Romania. One of the reasons lie in the fact that people forgot what an earthquake can do (as they also did prior to the 1940 and 1977 events). That is why special tools are necessary to address the needs for education and awareness in a technologically oriented society. In a world where information delivered through social media travels much faster than seismic waves, scientists need to adapt and be more present as an authoritative and relevant source of information. In this context, a partnership that brings together the unique expertise of geoscientists, visual designers and digital content developers was established, in order to develop and deliver a modern and innovative product: a Mobile Earthquake Exhibition (MOBEE). MOBEE aims to mobilize wide public as well as media and decision makers to increase earthquake preparedness by delivering and wisely spreading earthquake information and scientific explanations related to this natural hazard. The exposition makes use of new digital technologies (mobile apps, mapping tools or touch screen devices) but also explores the interplay between science and art, or more precisely how visual art can help better explain and transmit science concepts and generate new research and visual communication tools about seismic safety. [ABSTRACT FROM AUTHOR]

Earthquakes represent a real threat in Romania. They can cause important damages, loss of lives, socio-economic as well as cultural losses. The National Institute for Earth Physics (NIEP) is the only governmental organization responsible for monitoring the seismic activity on Romania's territory. NIEP provides different kind of information minutes to hours after the occurrence of a significant earthquake in Romania: near realtime information (location, depth and magnitude), ground shaking parameters and maps with the intensity of the shaking, post-event parameters, reports and macroseismic intensities. To issue such information, NIEP has been developing since 1980 one of the largest seismic networks in Europe, the Romanian Seismic Network (RSN). At present, RSN consists of 115 seismic stations equipped with velocity and accelerometer sensors and two seismic arrays. The increase of the density of the stations within RSN in the last decade led to a significant increase of the number of seismic events detected and located in Romania. RSN also provides valuable information for emergency managers in case of earthquake disaster, as it can provide rapid initial estimates and updated estimates of the location and extend of damage. [ABSTRACT FROM AUTHOR]