Southern Javakhet Earthquake Swarm. Stress Tensor Orientation Derived from Focal Mechanism Data

  • A. K. Tovmasyan
Part of the Advances in Natural and Technological Hazards Research book series (NTHR, volume 12)

Abstract

The earthquake swarm which occurred in 1996, in the period from May 29 to June 9, was recorded by both analog and digital stations and more than 120 small earthquakes (M< 2.5) were recorded by Armenian and Georgian networks during that time. Focal mechanisms for 19 relatively strong events were determined using first polarities of direct P waves. The variety of mnethods was used to analyze focal mechanism solutions. Based on obtained results one may conclude that these earthquakes are not related to well known and mapped active faults. Using Gepart and Forsuth’s improved method the regional stress tensor was determined.

We have analyzed in detail a sequence of earthquakes in Javakhet Upland and find some peculiarities of that. A detailed study of the earthquake catalogue showed that this swarm as some of preceding ones, was followed by relatively strong earthquake in Iran and Turkey

Keywords

Strong Earthquake Active Fault Focal Mechanism Earthquake Catalogue Nodal Plane 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 2000

Authors and Affiliations

  • A. K. Tovmasyan
    • 1
  1. 1.National Survey for Seismic Protection DavidashenYerevanArmenia

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