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Since its foundation, the Institute of Geodynamics "Sabba S. Stefanescu" of the Romanian Academy focused its interest on fundamental research imposed by the tasks implied by the Priority Program of the Romanian Academy, "Complex geophysical research in geodynamically active areas concerning especially the Vrancea seismogenic area", regarding particularly:

• the study of space-time variations of some parameters causally linked to the cumulating of stresses responsible for earthquakes occurrence;

• crustal deformations monitoring (relative displacement of tectonic blocks);

• tectonic hazard studies;

• the monitoring of space-time variations of the gravitational, geomagnetic, geoelectric fields and of earth crust tilts;

• the creation and permanent maintaining at an international level of a mobile specialized equipment for complex studies in geodinamically active areas (seismoactive areas, landslides, underground cavities collapses, areas that became geodynamically active because of anthropic activity);

• modeling of the thermo-mechanical evolution of the lithosphere;

• non-linear analysis of geodynamic systems.

At present, the Institute has a network of observatories and observation points, structured in profiles and geodynamics polygons, all having as a main purpose a better knowledge of phenomena leading to stress cumulating/ triggering in geodynamically active areas, with a special concern for the geodynamically active area of the Romanian Carpathians bend - the Vrancea seismogenic area, the network being concentrated in three geodynamics polygons: the Caldarusani-Tulnici Geodynamics Polygon, the Craciunesti-Deva, Sarmizegetusa Regia, Pades-Gorj Geodynamics Polygon and the Danube Delta - Mangalia Geodynamics Polygon (Fig. 5).

Among these polygons, a special place is occupied by the Caldarusani-Tulnici Geodynamics Polygon (Fig. 6) which includes - besides the laboratories for equipment gauging and aging, arranged in the framework of the Caldarusani Geodynamics Observatory, in the basement of the group of buildings that constitute the headquarters of the IG"SSS"AR (Fig. 7) and in the basement of the headquarters of the Romanian Academy - several micropolygons consisting of over 200 observation points, that allow the performing of repeated measurements, usually at 6 months up to 5 years intervals, and of underground laboratories, which allow data acquisition - within the limits of the possible, without interruption - corresponding to variations in the crust tilt and in the gravity, the magnetic and the electric fields.

A complex information is thus obtained on the physical parameters causally linked to earthquake cumulating/triggering in the hypocenters of the Vrancea area, a veritable natural laboratory of geodynamics (Fig. 8), the seismicity of the zone being monitored by the seismological network that belongs to the National Institute for Earth Physics of the Ministry of Education and Research. The observation points in the framework of the micropolygons are included in the first order national networks (the national geodetic network and the magnetic and gravimetric fields observation networks).

The location of the Vrancea Natural Laboratory for Geodynamics Among these micropolygons, the most important one - the Micropolygon I Tulnici - is situated in the Vrancea geodynamically active area (Fig. 9) on both sides of the contact on which the hypocenters of the Vrancea seismogenic area are situated, till a depth that may exceptionally exceed 180 km.

The Craciunesti-Deva, Sarmizegetusa-Regia, Pades-Gorj Geodynamic Polygon is constituted, in its northern part, of a set of underground observatories including laboratories situated at depths exceeding sometimes 500 m below the soil surface, where the sensors are located far from any influences of anthropic activities and at a distance of about 300 km of the Vrancea geodynamically active area; these laboratories, which allow recordings that are subject only to low perturbation by parasite noises, have the role to provide a valuable reference information.

The Danube Delta - Constanta Polygon is dedicated to the monitoring of actual phenomena of sedimentation / erosion dynamics, specific to the river water / marine water / crust contact.

In the framework of the Institute, activities are performed by work groups directing their efforts to:

• the study of space-time evolution of the relative displacements between blocks which are in contact in the Vrancea geodynamically active area, with a special concern for the Tulnici-Gresu profile;

• the design of the methodology for an optimal emplacement of sensors able to highlight physical parameters causally linked to stress cumulating/ triggering in geodinamically active areas;

• the study of geomagnetic, gravity and geothermal fields space-time evolution; implications in Geodynamics;

• the study of possibilities to use information provided by the natural variations of the electromagnetic field, for a better knowledge of the tectonic blocks geometry, concerning especially certain geodynamically active areas;

• the study of the connections between volcanism and geodynamically active processes, with a special concern for connections with major tectonic sutures;

• the study of quantification criteria for ground motion severity; possibilities of elaborating a complex criterion which should take into account both instrumental and macroseismic criteria.

The research activity is coordinated by the Scientific Council of the Institute, which includes 4 members of the Romanian Academy. The Institute has a research potential constituted of 36 attested researchers, 18 teaching professors, 28 Ph.D.s, as a Graduate Studies Organizing Institute, it prepares Ph.D. students, also with double supervision in collaboration with specialists from other countries, and it organizes yearly specialty courses in geodynamics, instrumentation, information processing.

The ensemble of works which assure the functioning of the equipment installed in the geodynamics observatories, supplies measurements on geodynamic profiles and networks, provides the prompt repairing of the equipment and, especially, assures the building and experimenting of high performance sensors in Geodynamics, of own construction or made worldwide, are carried out by a highly qualified research auxiliary personnel.

To maintain the level of the research at high level, specialists from other Romanian research units (The National Institute of Earth Physics, The National Institute for Building Research, the Geological Institute of Romania, the Geophysics Department of the Faculty of Geology and Geophysics, the Prospectiuni S.A. Enterprise, MINEXFOR Deva, etc.) are rallied to these activities, as well as specialists working in European research units with a similar profile (Institute de Physique du Globe - Paris, the Royal Observatory of Belgium, the Odendorf GeoObservatory of the Institute of Theoretical Geodesy of Bonn University, the Institute of Geophysics of the University of Karlsruhe, the Laboratory of Geophysics of Aarhus University, the United Institute of Earth Physics - Moscow, the Institute of Geophysics and Geology - Kishinew, the Institute of Geophysics - Bratislava, the Institute of Geodesy and Geophysics - Sopron, the Institute of Nuclear Research - Debrecen, a.s.o.),  respectively from Japan (the Institute of Seismology and Volcanology of Hokkaido University) and the United States (the United States Geological Survey).

• in June-July 2000, an European Mission of Geodynamics in the framework of which a group of 12 Romanian researchers visited the Schiltach Observatory of the Institute of Geophysics - Karlsruhe, the European Institute of Geodynamics - Luxembourg, the Royal Observatory of Belgium, the Odendorf GeoObservatory of the Institute of Theoretical Geodesy of the Bonn University, Institut de Physique du Globe - Paris, institutions in the framework of which the partners, Romanian and foreign - at the international co-operation concerning the Vrancea area - presented the achieved results, and

• during 2001, the "Caldarusani 2001" International Symposium, which allowed to some of the European collaborators of the Institute to make a direct contact to the works that are carried out in the framework of IG"SSS"AR and particularly in the framework of the Caldarusani Geodynamics Observatory and the Caldarusani-Tulnici Geodynamics Polygon, respectively.

Also during 2001, the "Sabba S. Stefanescu" Institute of Geodynamics of the Romanian Academy founded in cooperation with the United Institute of Earth Physics "O.Yu.Schmidt" of the Russian Academy of Sciences, the International Virtual Laboratory of Geodynamics, an international laboratory open to the participation of researchers with preoccupations in this domain, from Romania and Russia, as well as from other countries. The International Virtual Laboratory of Geodynamics, supported by UNESCO - Paris, is currently becoming an international network of specialists activating in institutes interested in geodynamics. Up to this day, specialists from many other institutions have expressed their wish to join the Virtual International Laboratory of Geodynamics, from Romania (the Geodynamics Group in the Section for Oil, Mines and Geonomy of the Academy of Technical Sciences of Romania, The National Institute of Earth Physics, the Institute for Fine Mechanics, the National Institute for Building Research), from Germany (the Institute of Geophysics of the University of Karlsruhe), from the Republic of Moldova (the Institute of Geophysics and Geology of the Academy of Sciences in Chisinau) and from France (Institut de Physique du Globe - Paris, le Département de Géophysique Appliquée de l’Université Pierre et Marie Curie, Académie de Paris) - the sequence by which the Laboratory extension is to occur will be analyzed by the founders of the Laboratory in March-April 2002.

The "Sabba S. Stefanescu" Institute of Geodynamics of the Romanian Academy was distinguished in 2000, by the Romanian Academy and the National Agency for Science, Technology and Innovation with the Diploma and the title of Institute of Excellency and, within the framework of the analysis performed in 2001 on the results of the research activity in the research institutes of the Romanian Academy, IG"SSS"AR was also classified as an Institute of Excellency.