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First results about crustal models were obtained from various geophysical and seismological methods applied in Romania in the last part of XX century. A thorough interpretation of these data lead to the first partial models of crustal structure in the western part of Romania. In the first years after 2000 two regional seismic refraction lines were performed within a close cooperation with German partners from University of Karlsruhe. One of these lines is Vrancea 2001, with 420 km in length, almost half of the events being recorded in the Transylvanian Basin. The interpretation of this line give a first look at the crustal structure in central Romania based on seismic data recorded along the profile. The structure of the crust along the seismic line revealed a very complicated crustal structure beginning with Carpathians Orogen and continuing in the Transylvanian Basin. As a result of the development in the last ten years of the seismic network, some 100 permanent broadband stations are now continuously operating in Romania. The data gathered so far is valuable for seismicity and crustal structure studies, especially for the western part of the country, where this kind of data was sparse until now. Complementary to this national dataset, maintained and developed in the National Institute for Earth Physics, new data emerged from temporary networks established during the joint projects with European partners in the last decades. Between 2009 - 2011 a temporary network of 33 broadband seismic stations were deployed and autonomously operated in an area covering the western part of Romania. The results show a thin crust for stations located in the eastern part of Pannonian Basin (28-30 km). In the Apuseni Mountains the Moho discontinuity can be found between 31 to 33 km depth. The stations within the Southern Carpathians are characterized by deeper crustal depths of about 33-36 km. Three lines crossing the western part of Romania are developed with 2D models of the variation of the seismic velocity in depth and the position of Moho boundary. The Moho boundary coincide generally with the isoline of seismic transverse velocity in depth of about 3.80 km/s. In the last chapter of the paper, fault systems in the study region are presented, their regional peculiarities as they appear in the available studies, projected on the local tectonic structure for each of the areas under examination. [ABSTRACT FROM AUTHOR]

The Vrancea zone is an area of concentrated seismicity at intermediate depths (60-200 km) beneath the bending area of the South-Eastern Carpathians in Romania. The purpose of the paper is first to find historic data related to the four selected Vrancea earthquakes occurred on 26 November 1829 (Mw 7.3), 1 May 1893 (Mw 6.2), 17 August 1893 (Mw 7.1) and 31 August 1894 (Mw 7.1). Next, to gather all available historic information about those events, analyze it, assess/or convert the intensity using the Medvedev-Sponheuer-Karnik (MSK-64) scale. Further, to compile corresponding macroseismic maps for these earthquakes applying an optimized interpolation method (Kriging). The macroseismic effects distribution has been compared to the distribution of intensity in cases of instrumentally registered strong 20th century Vrancea events of 1940 (Mw 7.7), 1977 (Mw 7.4) and 1986 (Mw 7.1) in order to highlight possible correlation between the main earthquake parameters - magnitude, source depth and macroseismic intensity. [ABSTRACT FROM AUTHOR]

In order to remain essential cultural and educational institutions, exhibitions and museums need to adapt to the times we live in and to the pace of technology and human interests. Through this paper we present our own experience and research in developing a state-of-the art earthquake related exhibition that meets the demands of our times and efficiently addresses a large and diverse target audience. The MOBEE (MOBile Earthquake Exhibition) Project tackles a very problematic topic in regard to the present and future of Romania: the key role of education, in the perspective of a future major earthquake. The project is the only initiative of this kind in Romania, a country where the lessons of previous destructive earthquakes (of 1940 and 1977) seem to be neglected. One of the main goals of the exhibition is to provide a reliable, attractive and up-to-date source of information regarding earthquakes, leading to mitigation by education. The initiative translates modern approaches into science, arts and computer science into end-products with a direct impact in forming (awakening) and developing the interest for earth science. We provide an insight on how and why new technologies and concepts like large scale 3D printed maps and models, digital animations and app development, hands-on experiments or flexible content were put to use. We hope that by sharing our experience we can help and stimulate other similar initiatives and propagate the mobile exhibition concept, as form of reaching the nowadays audiences (beside the online environment, which we also cover). [ABSTRACT FROM AUTHOR]

The study area is located at the contact between the Apuseni Mountains (Western Carpathians) with Pannonian Depression-to the west and with Transylvanian Depression - to the east. The eastern limit is marked by the Eastern Carpathians. The current tectonic activity is manifested by an uplift of the Carpathian Orogeny in relation to neighboring units, particularly the Pannonian Depression. The main seismological active areas are on the edge of the Pannonian Basin and in contact with the basement of Apuseni Mountains and Eastern Carpathians. Historical data suggests two potential earthquake magnitudes Mw >6, one of magnitude 6.2 (Mw) and one with magnitude 6 (Mw). Generally, the characteristics earthquakes of the area have magnitude Mw=5.6. We expect that the horizontal components of the movement (generated by the uplift of the Carpathians) to produce a compressive stress, as shown by focal mechanism solutions. [ABSTRACT FROM AUTHOR]

During October 2013 a swarm of seismic events originated in the NW Galati area, hence a striking number of earthquakes (a few hundreds), having a magnitude under 4.0 (on the Richter scale), generally associated with the fault system from this seismogenic area, previously known as active. Until that very moment, the seismic activity level had been significantly reduced. The great number of seismic events having the epicenter in crustal depths of less than 10 km), along a brief period of time, in an area known as relatively active only to the experts in this field, as well as the impact brought upon the local communities got researchers attention, thus resulting in the subject for an integrated GNSS and seismotectonic study of the NW Galati seismogenic area. Therefore, complex studies have taken place in the epicentral area and in the nearby regions, within a brief period of time. Those studies have been accompanied by a GPS campaign which also continued in 2014 and was followed by a third campaign in the summer of 2015. Preliminary results of the first three campaigns will be mentioned in this paper. [ABSTRACT FROM AUTHOR]

As a result of the continuous development in the last ten years of the network of the permanent broadband stations in Romania, valuable data for seismicity and crustal structure studies is now available, especially for the western part. Complementary to this national dataset, maintained and developed in the National Institute for Earth Physics, new data emerged from temporary networks established during the joint projects with European partners in the last decades. Such a joint project between University of Leeds, UK and National Institute for Earth Physics, Romania (South Carpathian Project - SCP), deployed 33 broadband seismic stations autonomously operated in an area covering the western part of the country and which continuously provided data for two years (2009-2011). This project offered a good opportunity to study the crustal structure of western part of Romania. The receiver function technique and a joint inversion method of receiver function and Rayleigh wave dispersion are employed in order to derive the 2D seismic velocity models for several seismic station locations. The results show a thin crust for stations located in the eastern part of Pannonian Basin (28-30 km). The stations within the Southern Carpathians are characterized by crustal depths of about 31-36 km. In the Apuseni Mountains the Moho discontinuity is replace by a transition zone extended between 31 to 33 km depth. Models of the variation of the seismic velocity in depth are developed along 3 lines crossing the western part of Romania. On the first 2 lines the Moho limit is placed and it coincide generally with the isoline of seismic transverse velocity of about 3.75 km/s. [ABSTRACT FROM AUTHOR]

Seismic stations are fundamental components in the analysis of earthquakes; they help us understand both the phenomenon and its effects on an ever complex society. Seismic recordings highly contribute to risk mitigation, through hazard analysis or influence on seismic codes, however the more we study these recordings and new data, the more we see limitations in our understanding. An ideal case would involve a very dense network of stations in inhabited areas, but in reality a prioritization must be made, due to the high costs associated and other restrictions. Through this study we tackle the prioritization problem differently than before; we propose a methodology that combines both data regarding risk estimates and characteristics of seismic stations within a network, in order to generate an index to describe the need of seismic monitoring, for areas that present social interest. The methodology relies on a weighting scheme applied to spatial datasets referring to aspects like: distance of inhabited place to seismic stations, seismic station's quality, estimated number of damaged buildings and uncertainties. The resulted index, when represented on a map, shows features like: hotspots -- areas where, due to high uncertainties and important loss estimates there is a need of seismic stations; well- instrumented sites. We apply the methodology to the Romanian Seismic Network, therefore providing future development recommendations. The recently installed Near Real-Time System for Estimating the Seismic Damage in Romania is used, with relevant scenarios of major earthquakes, in order to provide loss estimates for buildings. Results are plotted on relevant maps and significant conclusions are presented. [ABSTRACT FROM AUTHOR]

Earthquakes from Fagaras seismic zone are originating in the Southern Carpathians area and their foci are located at East and West of the Olt Valley. The most important events of the studied are is the seimic sequence from October 1916 of 6.4 (Mw) observed maximum magnitude. The earthquakes alignments are situated at the contact between the main tectonic units: Getic and Supragetic nappes and Danubian domain and at the contact between these three main cretaceous units with Moesian Platform. Also there are earthquakes alignments along Topolog Valley, Luncavatu Valley, Cerna Valleys. The seismogenic zone Olt Valley is characterized by a dominant compressional stress regime. Mostly, fault plane solutions belong to reverse component faulting (pure reverse fault and reverse fault with a strike-slip component) with tension axis almost vertical and pressure axis quasi-horizontal characterizes most of the major events, only two solutions showing strike-slip faulting. [ABSTRACT FROM AUTHOR]