WP 3.1 Foreshocks and development of new warning algorithms

Start date or starting event:


Lead contractor:


Participants:                                                UU,  IMOR



Detailed study of the foreshock activity and comparing with existing and new models of the earthquake nucleation process leading to the definition of new precursory parameters involving more of the microearthquake source parameters.




The observations are the 6 largest earthquakes within SISZ together with the 175,000 microearthquakes during the period 1990-2001 as recorded by the Icelandic microearthquake network operated by the Icelandic Meteorological Office. All these observations  have been inverted for source parameters.


Methodology / work description:

The foreshock activities will be analyzed by use of multievent locations (accurate absolute and relative location  in combination with reanalyzed fault plane solutions and dynamic source parameters.  Key questions are the role of the foreshocks (concentrating stress or uniforming stress) and their relation to aseismic fault movements (especially accelerating creep). This work will result in detailed physical information about the foreshocks and the crustal processes which will be related to different models of earthquake nucleation. This is expected to lead to new aspects in monitoring the microearthquakes for possible precursory effects. Eventually new earthquake warning parameters will be defined and tested in earthquake warning algorithms.



Deliverables including cost of deliverable as percentage of total cost of the proposed project:


Detailed documentation of the foreshock activity prior to the six largest earthquakes in Iceland during the last 10 years.

M15  Re  PU  0,4%


New short-term warning algorithms will be introduced in the Early warning and information system for testing, during the project time.

M15  O   PU  0,6%


An article describing the foreshock character, the statistical significance and relation to the various source information.

M15  Re  PU  0,4%


A complete automatic earthquake warning algorithm based on the understanding acquired during PREPARED will be presented. 

M24  O   PU  0,4%


Input of the Early warning and information system for testing at the end of the project to IMOR.

M24  O   PU  1,2%



Milestones: Delivery of the above items at the date indicated.