Advertisement

Pure and Applied Geophysics

, Volume 176, Issue 1, pp 65–95 | Cite as

Structural and Geodynamic Ideas on the Galati-Izvoarele Seismic-Prone Area (Eastern Romania)

  • Lucian BesutiuEmail author
  • Mihail Diaconescu
  • Luminita Zlăgnean
  • Andreea Craiu
Article
  • 147 Downloads

Abstract

The Galati-Izvoarele region, located in eastern Romania, came into the public attention relatively recent, when hosted an unusual intense earthquake sequence. During September–November 2013, several hundred shallow crust earthquakes were recorded in the area. There were several attempts to explain the phenomenon, and hypotheses more or less documented have been formed. Some speculations occurred on the potential connection between the seismic swarm and oil industry activities. The paper summarizes the results of local geophysical surveys conducted in the area, jointly analysed with the observed seismicity. The main results of the study reveal the Galati-Izvoarele region as a seismic-active area belonging to the northwest prolongation of North Dobrogea mobile zone. The earthquakes were generated mainly in a highly fragmented local graben-like structure, transversally superposed on the descending slope of the North Dobrogea Promontory. The graben fault system was and might be (re)activated each time when tectonic forces acting in the Carpathians foreland intensify. Changes in the intensity of tectonic forces may reflect in the slip acceleration along Peceneaga–Camena Fault, as observed at the Baspunar Geodynamic Observatory. For example, the paroxysmal phase of the Galati-Izvoarele swarm was shortly preceded by a significant increase of the Peceneaga–Camena Fault slip rate recorded at Baspunar Geodynamic Observatory. To conclude, the Galati-Izvoarele region must be seen as a seismic-prone area and any significant increase of the tectonic stress in the Carpathians foreland may generate another seismic sequence in an unpredictable future.

Keywords

Seismic hazard tectonics geodynamics gravity geomagnetism modelling Galati-Izvoarele area Romania 

Notes

Acknowledgements

Most of the high time-consuming computations benefitted the SEDD cybernetic infrastructure achieved within an EU funded project through the grant POS CCE O 2.1.2. ID 593 (contract 184/2010). We are much indebted to Prof. Marian Ivan, Faculty of Geology and Geophysics, University in Bucharest, for fruitful discussions and suggestions provided. The authors also wish to thank the two anonymous reviewers for their constructive critics that considerably help improving the manuscript.

References

  1. Banks, C. J., & Robinson, A. (1997). Mesozoic strike-slip back-arc basins of the western Black Sea region. In A. G. Robinson (Ed.), Regional and petroleum geology of the Black Sea and surrounding region (Vol. 68, pp. 53–62). Tulsa: AAPG Memoir.Google Scholar
  2. Besutiu, L. (1997). Contributii la elaborarea unui model geologic al zonei de trecere de la uscatul Dobrogei de Nord la platforma continentalǎ a Mǎrii Negre pe baza interpretǎrii datelor gravimetrice si magnetometrice cu ajutorul modelelor de simulare (Contributions to the unveiling of the geological structure of the transient zone between the North Dobrogea inland and the Black Sea offshore, based on the gravity and geomagnetic data interpretation using numerical simulation models). Dissertation, University of Bucharest.Google Scholar
  3. Besutiu, L., Nicolescu, A., & Vl, Zorilescu. (2001). Considerations on the gravity system of Romania. Bur Grav Int, Bull Inf, 89, 35–47.Google Scholar
  4. Besutiu, L., Orlyuk, M., Zlagnean, L., Romenets, A., Atanasiu, L., & Makaraenko, I. (2014). Peceneaga–Camena Fault: Geomagnetic insights into an active tectonic contact. Geophysical Journal, 1(36), 133–144. (ISSN 0203-3100).Google Scholar
  5. Besutiu, L., & Zlăgnean, L. (2010). Monitoring dynamics of an active plate boundary: Peceneaga–Camena Fault. Geophysical Research Abstracts, 12, EGU2010-1514.Google Scholar
  6. Besutiu, L., & Zlăgnean, L. (2014). Infrastructure for monitoring geodynamic processes and related seismic hazard within SE Carpathians. 10th ELSEDIMA, international conference, Cluj-Napoca, Romania, September 18th–19th, 2014, Book of Abstracts, pp. 17–18.Google Scholar
  7. Besutiu, L., & Zugrăvescu, D. (2004). Considerations on the Black Sea opening and related geodynamic echoes in its NW inland as inferred from geophysical data interpretation. Ukrainian Geologist, 3, 51–60.Google Scholar
  8. Blakely, R. J. (1995). Potential theory in gravity and magnetic applications (p. 441). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
  9. Bratt, S., & Bache, T. C. (1988). Locating events with a sparse network of regional arrays. Bulletin of the Seismological Society of America, 78, 780–798.Google Scholar
  10. Bratt, S., & Nagy, W. (1991). The LocSAT program. San Diego: Science Applications International Corporation.Google Scholar
  11. Calistru, V., & Munteanu, C. (1974). Cartografie matematicǎ:133-198, Universitatea Tehnică de Construcţii Bucureşti (Mathematical Cartography, Technical University of Civil Engineering Bucharest).Google Scholar
  12. Caputo, M. (1967). The gravity field of the earth. From classical to modern methods (p. 216). Oxford: Elsevier Academic Press.Google Scholar
  13. Cassinis, G. (1930). Sur l’adoption d’une formule internationale pour la pesanteur normale. Bulletin Géodesique, 26, 40–49.CrossRefGoogle Scholar
  14. Cassinis, G. (1931). Tables des valeurs de la pesanteur normale internationale. Bulletin Géodesique, 33, 313–320.CrossRefGoogle Scholar
  15. Chirilă, C., & Mihalache, R. M. (2011). Coordinate transformations for integrating local map information in the new geocentric European system, for urban real-estate cadastre achievement. Series Mathematical Modelling in Civil Engineering (Technical University of Civil Engineering Bucharest), 4, 159–165.Google Scholar
  16. Cloetingh, S., Bada, G., Matenco, L., Lankreijer, A., Horváth, F., & Dinu, C. (2006). Modes of basin (de)formation, lithospheric strength and vertical motions in the Pannonian–Carpathian system: Inferences from thermo-mechanical modeling. In D. G. Gee & R. A. Stephenson (Eds.), European lithosphere dynamics (pp. 207–224). London: The Geological Society of London.  https://doi.org/10.1144/gsl.mem.2006.032.01.12.Google Scholar
  17. Craiu, A., Craiu, M., Diaconescu, M., & Mărmureanu, A. (2016). Seismic swarm recorded in Galati area, Romania: Focal mechanism solutions. Acta Geodaetica et Geophysica.  https://doi.org/10.1007/s40328-016-0161-9.Google Scholar
  18. Crowley, Q. G., Marheine, D., Winchester, J. A., & Seghedi, A. (2000). Recent geochemical and geochronological studies in Dobrogea, Romania. Joint meeting of EUROPROBE TESZ and PACE projects in Zakopane and Holy Cross Mountains, Poland, September 2000, Abstracts: 16–17, pp. 16–23.Google Scholar
  19. Dinter, G., & Schmidt, G. (2001). Three dimensional plate kinematics in Romania. Natural Hazards, 23, 389–406.CrossRefGoogle Scholar
  20. Douglas, A. (1967). Joint epicentre determination. Nature, 215, 47–48.CrossRefGoogle Scholar
  21. Fullagar, P. K., Hughes, N. A., & Paine, J. (2000). Drilling constrained 3D gravity inversion. Exploration Geophysics, 31, 17–23.CrossRefGoogle Scholar
  22. Fullagar, P. K., & Pears, G. A. (2007). Towards geologically realistic inversion. Advances in geophysical inversion and modeling. In B. Milkereit (Ed.) Proceedings of exploration 07: fifth decennial international conference on mineral exploration, pp. 444–460.Google Scholar
  23. Grădinaru, E. (1984). Jurassic rocks of north Dobrogea. A depositional–tectonic approach. Revue Roumaine de Géologie Géophysique et Géographie Serie Géologie, 28, 61–72.Google Scholar
  24. Grădinaru, E. (1988). Jurassic sedimentary rocks and bimodal volcanics of the Cirjelari-Camena outcrop belt: Evidence for a transtensile regime of the Peceneaga–Camena Fault. St Cerc Geol Geofiz Geogr Ser Geol, 33, 97–121.Google Scholar
  25. Hinze, W. J., Von Frese, R. B., & Saad, A. H. (2013). Gravity and magnetic exploration. Principles, practices and applications (p. 512). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
  26. Hippolyte, J.-C. (2002). Geodnamics of Dobrogea (Romania): New constraints on the evolution of the Tornquist-Teisseyre Line, the Black Sea and the Carpathians. Tectonophysics, 357, 33–53.CrossRefGoogle Scholar
  27. Hippolyte, J.-C., Sǎndulescu, M., Bǎdescu, D., & Bǎdescu, N. (1996). L’activité d’un segment de la ligne Tornquist-Teisseyre depuis le Jurassique supérieur: La faille de Peceneaga–Camena (Roumanie). Comptes Rendus Mathematique Academie des Sciences Paris, 323(Série IIa), 1043–1050.Google Scholar
  28. Ianovici, V., Giusca, D., Mutihac, V., Mirauţǎ, O., & Chiriac, M. (1961). Aperçu général sur la géologie de la Dobrogea. Assoc Géol Carp-Balk V-éme Congr D Dobrogea, p. 92.Google Scholar
  29. Ioane, D., Serban, A., Diaconescu, M., Chitea, F., & Caragea, I. (2015). High seismicity sequence in the Izvoarele area (Galati county)—Romania. In Proceedings of the 15th international multidisciplinary scientific geoconferences SGEM2015. Google Scholar
  30. Lăzărescu, V., & Popescu, M. N. (1984). Correlation paleo-recent tectonics at the Eastern Carpathians arc bend. Rev Roum Géol Géophys Géogr Ser Géophysics, 28, 3–18.Google Scholar
  31. Leever, K. A., Matenco, L., Bertotti, G., Cloetinghn, S., & Drijkoningenn, G. G. (2006). Late orogenic vertical movements in the Carpathian Bend Zone—seismic constraints on the transition zone from orogen to foredeep. Basin Research, 18, 521–545.  https://doi.org/10.1111/j.1365-2117.2006.00306.x.CrossRefGoogle Scholar
  32. Li, Y., & Oldenburg, D. W. (1998). 3-D inversion of gravity data. Geophysics, 63, 109–119.CrossRefGoogle Scholar
  33. Martin M., F. Wenzel, and CALIXTO Working Group. (2006). High-resolution teleseismic body wave tomography beneath SE Romania: II. Imaging of a slab detachment scenario. Geophysical Journal International, 164, 579–595.  https://doi.org/10.1111/j.1365-246X.2006.02884.x.CrossRefGoogle Scholar
  34. Matenco, L., Bertotti, G., Leever, K., Cloetingh, S., Schmid, S. M., Tărăpoancă, M., et al. (2007). Large-scale deformation in a locked collisional boundary: Interplay between subsidence and uplift, intraplate stress and inherited lithospheric structure in the late stage of the SE Carpathian evolution. Tectonics, 26, 1–29.CrossRefGoogle Scholar
  35. Milsom, J., & Eriksen, A. (2014). Field geophysics (4th ed., p. 287). Oxford: Wiley.Google Scholar
  36. Mirăuţă, O., & Mirăuţă, E. (1962). Palaeozoic of the southern Mǎcin Mountains (Cerna-Hamcearca region). D S Institute of Géolofy, XLIV, 129–142. (in Romanian).Google Scholar
  37. Mirăuţă, O., Mutihac, V., Bandrabur, T., & Drăgulescu, A. (1966). Geological map scale 1:200.000 (Vol. 38). Comitetul de Stat al Geologiei, Institutul Geologic: Tulcea.Google Scholar
  38. Mrazec, L. (1910). Discussion sur l’existance des roches vertes en Carpathes. Dări de Seamă ale Institutului Geologic, II, 13–27.Google Scholar
  39. Mrazec, L. (1912). Sur la ligne de chevauchement Peceneaga—Camena. Dări de Seamă ale Institutului Geologic, III, 163–165.Google Scholar
  40. Mrazec, M., & Pascu, R. (1896). Note sur la structure géologique des environs du village d’Ortachioi (Dist Tulcea, Arr. Babadag). Bulletin de la Société du Physique, Bucuresti, 12, 82–96.Google Scholar
  41. Nicolescu, A., & Rosca, V. (1992). The Bouguer anomaly map of Romania, Scale 1:1.000.000. Romania: Geological Institute of Romania.Google Scholar
  42. Oaie, G. (1986). Sedimentology of the pebbly red sandstone facies association within the Carapelit Formation, North Dobrogea. Revue Roumaine de Géologie Géophysique et Géographie Serie Géologie, 30, 59–70.Google Scholar
  43. Oaie, G., & Seghedi, A. (1992). Upper Palaeozoic continental sedimentation in North Dobrogea, Romania. Terra Abstracts, Abstracts Supplement no. 2 to TERRA NOVA, Graz 4, p. 49.Google Scholar
  44. Paeckelman, W. (1935). Probleme des Varisticums der Dobrudscha. Zeitschrift der Deutschen Geologischen Gesellschaft Berlin, 87/1, 507–522.Google Scholar
  45. Paraschiv, D. (1975). The geology of the hydrocarbon deposits in Romania. Studii Tehnice şi Economice Seria A, 10, 363. (in Romanian).Google Scholar
  46. Paraschiv, D., Paraschiv, C., Andrei, C., Popescu, M., & Danet, N. (1983). On the pre-Neogene formations in the North-Dobrogean promontory. Annual Institute of Geology and Geophysics, 59, 19–27.Google Scholar
  47. Parker, R. L. (1973). The rapid calculation of potential anomalies. Geophysical Journal of the Royal Astronomical Society, 31, 447–455.CrossRefGoogle Scholar
  48. Popa, M., Oros, E., Dinu, C., Radulian, M., Borleanu, F., Rogozea, M., et al. (2016). The 2013 earthquake swarm in the Galati Area: First results for a seismotectonic interpretation. In R. Vacareanu & C. Ionescu (Eds.), The 1940 Vrancea earthquake. Issues, insights and lessons learnt. Springer natural hazards (pp. 253–265). Cham: Springer.CrossRefGoogle Scholar
  49. Răileanu, V. (2009). Caracterizarea geologica si parametrii elastici ai amplasamentelor statiilor seismologice si de accelerometre din reteaua Institutului National de C-D pentru Fizica Pamantului. In G. Mărmureanu (Ed.), Cercetari privind managementul dezastrelor generate de cutremurele romanesti. Romania: Editura Tehno Press. (ISBN: 973-702-701-9; in Romanian).Google Scholar
  50. Roman, C. (1970). Seismicity in Romania—evidence for the sinking lithosphere. Nature, 228, 1176–1178.CrossRefGoogle Scholar
  51. Rosca, V., & Besutiu, L. (2000). Romanian annual progress report for the UNIGRACE project. Reports on Geodesy, 5(51), 71–76.Google Scholar
  52. Rotman, D. (1917). Das Eruptif massif von Greci (jud. Tulcea - Dobrogea). Anuarul Institutului Geologic al României Bucharest, VII, 1–174.Google Scholar
  53. Săndulescu, M. (1978). The Moesian platform and the North Dobrogean orogen. In M. Lemoine (Ed.), Geological Atlas of Alpine Europe and Adjoining Areas (pp. 427–460). Amsterdam: Elsevier.Google Scholar
  54. Săndulescu, M. (1980). Analyse géotectonique des chaînes alpines situées autour de la Mer Noire occidentale. Anuarul Institutului de Geologie si Geofizica Bucharest, 56, 5–54.Google Scholar
  55. Săndulescu, M. (1984). Geotectonica Romaniei (Geotectonics of Romania) (p. 336). Virginia: Technica. (in Romanian).Google Scholar
  56. Săndulescu, M., & Visarion, M. (1988). La structure des plate-formes situées dans l’avant-pays et au dessous des nappes du flysch des Carpathes orientales. Stud Teh Econ Geofiz Bucharest, 15, 61–70.Google Scholar
  57. Saulea, E., Ghenea, C., Bandrabur, I., & Ghenea, A. (1967). The National Geological Map of Romania at the scale 1: 200.000, Focsani sheet. Institute of Geology and Geophysics.Google Scholar
  58. Seghedi, A. (1980). Metamorphic formations of north Dobrogea. Annals of the Academy of Romanian Mem sect Şt Bucharest, 2, 1–16.Google Scholar
  59. Seghedi, A. (1999). Petrological study of magmatic and metamorphic formations from Megina-Mircea Vodă Area (Dobrogea). Dissertation, University of Bucharest (in Romanian). Google Scholar
  60. Seghedi, A. (2012). Palaeozoic formations from Dobrogea and pre-Dobrogea—an overview. Turkish Journal Of Earth Sciences, 21, 669–721.Google Scholar
  61. Seghedi, A., & Oaie, G. (1995). Palaeozoic evolution of North Dobrogea. In Sǎndulescu et al. (Eds) Field guidebook, Central and North Dobrogea IGCP Project no. 369 ‘Comparative evolution of PeriTethyan Rift Basins’, Mamaia, pp. 5–75.Google Scholar
  62. Stănică, D., Stănică, M., & Visarion, M. (1986). The structure of the crust and upper mantle in Romania as deduced from magnetotelluric data. Rev Roum Geol Geopys Geogr Ser Geophysics, 30, 25–36.Google Scholar
  63. Tărăpoancă, M., Bertotti, G., Matenco, L., Dinu, C., & Cloething, S. (2003). Architecture of the Focşani Depression: A 13 km deep basin in the Carpathians bend zone (Romania). Tectonics, 22(6), 1074.  https://doi.org/10.1029/2002TC001486.Google Scholar
  64. Thébault, E., Finlay, C. F., Beggan, C. D., Alken, P., Aubert, J., Barrois, O., et al. (2015). International geomagnetic reference field: The 12th generation. Earth Planets and Space.  https://doi.org/10.1186/s40623-015-0228-9.Google Scholar
  65. van der Hoeven, A. G. A., Mocanu, V., Spakman, W., Nutto, M., Nuckelt, A., Matenco, L., et al. (2005). Observation of present-day tectonic motion in the Southeastern Carpathians: Results of the ISES/CRC-461 GPS measurements. Earth and Planetary Science Letters, 239, 177–184.CrossRefGoogle Scholar
  66. van der Hoeven, A. G. A., Schmitt, G., Dinter, G., Mocanu, V., & Spakman, W. (2004). GPS probes the kinematics of the Vrancea Seismogenic Zone. Eos Transactions American Geophysical Union, 85(19), 185–196.CrossRefGoogle Scholar
  67. Visarion, M., Săndulescu, M., Stănica, D., & Veliciu, S. (1988). Contributions à la connaisance de la structure profonde de la Platforme Moesienne en Roumanie. St Tehn Ec seria D (Geofizica), 15, 211–222.Google Scholar

Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.Institute of Geodynamics of the Romanian AcademyBucharestRomania
  2. 2.National Institute for Earth PhysicsMăgureleRomania

Personalised recommendations