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
Article

Abstract

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.

Keywords

Time Distribution Poisson Process Seismic Event Sedimentology Seismic Station 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. De Natale, G., Zollo, A., Del Gaudio, C., Ricciardi, G.P., Martini, M., 1984,Error Analysis in the Hypocentral Location in the Phlegraean Fields. Bull. Vulcanol.,47-2.Google Scholar
  2. Dobrovolski, J.P., Zubkov, S.I., Miachkin, V.I., 1979,Estimation of the Size of Earthquake Preparation Zones. Pageoph,117, p. 1025–1044.Google Scholar
  3. Kagan, Y.Y., Knopoff, L., 1976,Statistical Search for Non-random Features of the Seismicity of Strong Earthquakes. Phiys. Earth Planet. Int.,12, p. 291–318.Google Scholar
  4. ——, ——, 1981,Stochastic Synthesis of Earthquake Vatalogs. Journ. Geophys. Res.,86, p. 2853–2862.Google Scholar
  5. Kanamori, H., 1981,The Nature of Seismicity Patterns Before Large Earthquakes. M. Ewing Series, AGU Mon., n. 4, p. 1–19.Google Scholar
  6. Osservatorio Vesuviano, 1984,Rapporto sul bradisismo flegreo. Gennaio 1984.Google Scholar
  7. Parzen, E., 1962,Stochastic Processes. Holden Day, S. Francisco.Google Scholar
  8. Rikitake, T., 1975,Earthquake Precursors. Bull. Seism. Soc. Am.,65, p. 1133–1162.Google Scholar
  9. Scarpa, R., Zollo, A., 1984,Distribuzione spazio-temporale degli eventi sismici nell'area Mediterranea. Proc. Il Naz. Conv. GNGTS, CNR, Roma (in press.).Google Scholar
  10. Shlien, S., Toksoz, M.N., 1970,Clustering Model for Earthquake Occurrence. Bull. Seism. Soc. Am.,60, p. 1765–1787.Google Scholar
  11. Vere-Jones, D., 1970,Stochastic Models for Earthquake Occurrence. J.R. Stat. Soc.,32 (1, p. 1–45.Google Scholar
  12. Von Seggern, D., Alexander, S.S., Baag, C.E., 1981,Seismicity Parameters Preceding Moderate to Major Earthquakes. J.G. Res.,86, p. 8325–9351.Google Scholar

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

Personalised recommendations