Bulletin Volcanologique

, Volume 47, Issue 2, pp 201–207 | Cite as

Space-time distribution of small earthquakes at Phlegraean Fields, south-central Italy

  • E. Del Pezzo
  • G. De Natale
  • A. Zollo


A preliminary statistical analysis of the space-time distribution of small seismic events in the volcanic area of Phlegraean Fields, south-central Italy, was done on the basis of a catalogue of earthquakes recorded by the local seismic stations in the period January 1, December 31, 1983.

The non-random character of the sequence has been tested by matching the observed time-dstribution of seismic events with the theoretical Poisson process.

A clustered occurrence of seismic events seems to be the main cause of the departure from a Poisson process as the inter-arrival times distribution clearly shows.

Furthermore, the non-random behaviour of the events space-time distribution mainly due to quiescient and clustered recursive seismic phases could be studied by using the method proposed byVon Seggernet al. (1981). The analysis and the space-time diagrams confirm the swarm-type character of the entire seismic sequence.


Time Distribution Poisson Process Seismic Event Sedimentology Seismic Station 
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Copyright information

© Intern. Association of Volcanology and Chemistry of the Earth's Interior 1984

Authors and Affiliations

  • E. Del Pezzo
    • 1
  • G. De Natale
    • 1
  • A. Zollo
    • 1
  1. 1.Osservatorio VesuvianoErcolano (Naples)Italy

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