New Zealand Journal of Geology and Geophysics abstracts

---

Multiple-mainshock events and long-term seismogenesis in Italy and New Zealand

Frank Evison*

Institute of Geophysics
School of Earth Sciences
Victoria University of Wellington
P.O. Box 600
Wellington, New Zealand

David Rhoades

Institute of Geological & Nuclear Sciences
P.O. Box 30 368
Lower Hutt, New Zealand

*Deceased

Abstract  The phenomenon of the precursory scale increase (ψ), on which the three-stage faulting model of long-term seismogenesis is based, has previously been studied in relation to mainshock/aftershock events, and clusters of such events, in California, Greece, Japan, and New Zealand. The tectonic environments of the studied events have comprised subduction, continental collision, and continental transform. In Italy, the study is now extended to large multiplet-type events and to extensional tectonics. New Zealand provides further examples of large multiplets. The results show that multiplets, interpreted as multiple-mainshock events, are preceded by the same ψ-phenomenon as the types of event previously studied. ψ again provides estimates of the location, start time, and magnitude level of the multiplet. It is concluded that the long-term seismogenic process that explains previously studied occurrences of the ψ-phenomenon, occurs equally with multiplets, and in conditions of extensional tectonics.

Keywords  seismogenesis; multiplets; precursory seismicity; Italy; New Zealand

G04026; Received 24 June 2005; accepted 20 December 2005; Online publication date 22 August 2005
New Zealand Journal of Geology & Geophysics, 2005, Vol. 48: 523–536
0028–8306/05/4803–0523© The Royal Society of New Zealand 2005

PDF file of entire paper: Print-quality (1290K) | screen-quality (595K)

---

This year's abstracts | Journal home page | All abstracts | Publishing home page