Short Seminar 2012/11/07

日時: 2012年11月7日(水) 11:30-12:00
場所: 地震火山研究センターセミナー室(E411)
講演者: Mr. Gino Steven Gonzalez llama, Costa Rica
      Geologist, Volcanic Surveillance /National Seismological Network RSN
概要: JICA研修生のGino Gonzalez Ilamaさんに、2012年9月5日にコスタリカで発生したNicoya地震(Mw7.6)を紹介していただきました。



Title:Tectonic setting and worldwide unique position on the seismogenic zone,study case: Nicoya earthquake (Mw= 7.6), Costa Rica.
Gino González Ilama1,2

In Costa Rica there is an interaction between three tectonic plates, Coco, Nazca (oceanic crust) and Caribbean (continental crust), which are responsible for producing large numbers of earthquakes and many active volcanoes.
The world's largest earthquakes occur in the seismogenic zone (e.g. Valdivia, Chile, Mw = 9.5; Sumatra, Indonesia, Mw = 9.2; Tohoku, Japan, Mw = 9.0). From the geological records, Costa Rica sits atop this seismogenic zone; the reason why it facilitates the study and instrumentation in this region.
Historically, at least three major earthquakes occurred in the Nicoya Peninsula (1853,1900, 1950), so some researchers discussed the characteristic earthquake and recurrence period, causing positive and negative consequences. On 5 September 2012, as expected, a Mw 7.6 earthquake occurred in Nicoya Peninsula.
This earthquake caused a rise in the coast of 75 cm, several swarms in much of the country and increased activity of the active volcanoes of Nicaragua and Costa Rica.

1. Geologist graduate in the Central American of Geology School, University of Costa Rica.
2. Assistant in Volcanic Surveillance, Red Sismológica Nacional (National Seismological Network), Universidad de Costa Rica.