SCEC Award Number 15057 View PDF
Proposal Category Travel Only Proposal (SCEC Annual Meeting)
Proposal Title CSEP participation, including the Canterbury experiment, software for efficient testing, and hybrid models.
Name Organization
Matthew Gerstenberger GNS Science (New Zealand) David Rhoades GNS Science (New Zealand)
Other Participants
SCEC Priorities 2b SCEC Groups CSEP, EFP
Report Due Date 10/16/2015 Date Report Submitted 10/15/2015
Project Abstract
The award was for travel to the SCEC annual meeting only. Our associated activities included four main objectives: 1) Collaboration with the CSEP team in conducting and analyzing an experiment to retrospec- tively test forecasting models based on Coulomb stress calculations using data from the Canterbury earthquake sequence in the New Zealand CSEP testing center, and to subsequently test the models pro- spectively on future New Zealand earthquakes; 2) Preparation of software to demonstrate the efficient calculation of likelihood based consistency tests in CSEP experiments, so that efficient versions of these tests can be implemented in the CSEP testing centers; 3) Providing methods for generating optimal hy- brid earthquake forecasting models that can be made available to the wider research community. This includes hybridization of existing CSEP-compatible earthquake-rate forecasting models, and/or alarm- type forecasting models, or gridded data of seismicity-related variables, to produce new models with im- proved information value; 4) Participation in international CSEP activities, including the design of future experiments, and preparation of new models for testing in the CSEP framework. This also included partic- ipation by David Rhoades and Annemarie Christophersen in the CSEP workshop held at 2015 SCEC An- nual Meeting.
Intellectual Merit The activities in this project are directly relevant to the SCEC objectives for earthquake forecasting and predictability and development of the CSEP project, including the development of improved forecasting models and testing methods, and the use of hybrid methods to improve forecasting. Our activities are not solely focused on New Zealand, but rather on the general problems of earthquake forecasting and the common international CSEP methodology. Therefore there are substantial benefits for California resulting from our work.
Broader Impacts The collaborative CSEP project is making major advances to the development and testing of earthquake forecasting models on all time scales. Our contributions are a significant component of the overall interna- tional collaboration, from which all parties derive mutual benefits. The Canterbury earthquakes have pro- vided a useful data set on which to retrospectively test a range of models, which can subsequently be applied more generally in California and other regional testing centers.
Exemplary Figure Figure 1. Information gain per earthquake of multiplicative hybrid models relative to baseline SUP model in the testing period 2007-2014 in the New Zealand CSEP testing region. (Left) PPE and HBG models as at 1986, (Right) PPE and HBG models updated to 2006.

Explanation of terms: SUP: Stationary uniform Poisson; FLT: Fault in cell PPI: Proximity to plate interface; HBG: NZ national seismic hazard model background; PPE: proximity to past earthquakes; PMF: Proximity to mapped faults.