Journal of Radioanalytical and Nuclear Chemistry

, Volume 293, Issue 3, pp 769–781 | Cite as

Monitoring of radon anomalies in South-Eastern part of Romania for earthquake surveillance

  • M. ZoranEmail author
  • R. Savastru
  • D. Savastru
  • C. Chitaru
  • L. Baschir
  • M. Tautan


South-Eastern part of Romania has a highest potential seismic risk in Europe due to the earthquake-prone Vrancea zone placed at conjunction of four tectonic blocks in the South-Eastern part of Carpathian Arc. This paper is an attempt to analyze the development of radon pre-earthquake anomaly in relation with moderate seismic events in Vrancea area through permanent monitoring with solid state nuclear track detectors CR-39 detectors. Radon in air above the ground was measured during 1 year period (November 2010–October 2011) in four selected test sites: Vrancioaia (VRI) and Plostina (PLOR) located in Vrancea zone, and Muntele Rosu-Cheia and Bucharest. During sampling period recorded earthquakes that occurred mostly in Vrancea epicentral region were minor-moderate of moment magnitudes in range of \( 2.0 \le M_{w} \le 4.9 \). The average radon concentration in air above the ground measured with CR-39 detectors and 10 days period recorded simultaneously at all test sites, registered the following values: (1) in Vrancea area (similar in VRI and PLOR) was 1094.58 \( \pm \) 150.3 Bq/m3; (2) at Muntele Rosu-Cheia seismic station measured in a mountain tunnel laboratory was 3695.91 ± 440 Bq/m3; (3) at Bucharest station was 380.53 \( \pm \) 69.17 Bq/m3, and 10 days CRn fluctuations in the range of (88 \( \pm \) 40 to 912 \( \pm \) 130 Bq/m3). Clear radon anomalies, mostly at VRI and PLOR in Vrancea epicentral area as well as at Muntele Rosu-Cheia have been measured before seven minor earthquakes which were recorded in the range of moment magnitude \( 4 \le M_{w} \le 4.9 \) in Vrancea area. Temporal variation of radon in air near the ground have been examined in relation with meteorological parameters like as air temperature, relative humidity, air pressure and wind velocity. Permanent monitoring of radon concentration anomalies in seismic area Vrancea is an important issue as surveillance tool in the field of earthquake hazard for Romania.


Radon concentrations SSNTD CR-39 Vrancea seismic zone Romania 



This work was supported by the PN Program, Project: No. 09 27 01 03/2011-INOE of Romanian Ministry of Education, Research, Youth and Sport. We would like to thank to Radon Analytics, Bonn, Germany for delivering and chemical etching and optical counting of CR-39 used detectors.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2012

Authors and Affiliations

  • M. Zoran
    • 1
    Email author
  • R. Savastru
    • 1
  • D. Savastru
    • 1
  • C. Chitaru
    • 2
  • L. Baschir
    • 1
  • M. Tautan
    • 1
  1. 1.National Institute of Research and Development for OptoelectronicsBucharest MagureleRomania
  2. 2.Seismological Observatory Muntele Rosu-Cheia, National Institute of Research and Development for Earth PhysicsBucharest MagureleRomania

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