CRISIS2015 - PSHA
New!
A more recent version than CRISIS2015 called R-CRISIS is available, you can download it for free at http://www.r-crisis.com/
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Welcome to the Website of CRISIS2015.
This site is intended for CRISIS users and other parties interested in knowing about CRISIS. Thank you for your visit.
CRISIS2015 Program for computing Seismic Hazard
Brief description
CRISIS gives a friendly environment to calculate seismic hazard. The program computes seismic hazard using a probabilistic model that considers the earthquake occurrence probabilities, attenuation characteristics and geographical distribution of earthquakes. A friendly graphical interface facilitates data input.
Hazard results are mainly given, for each computation site, in terms of probabilities of exceeding a given intensity value in different time frames. It is also possible to obtain hazard results in terms of non-exceedance probability and equivalent exceedance rate. Details on the hazard computation algorithm can be found following the link.
Some of the main features of CRISIS are:
Earthquake occurrence
Earthquake occurrence can be modeled either as a Poissonian process or as a non-Poisson process. For the Poissonian case, CRISIS admits several types of magnitude-frequency relations: modified Gutenberg-Richter law, Characteristic Earthquake,and Generalized Poissonian model. For Non-Poissonian occurrences, CRISIS can work with a generalized Non-Poissonian model with which earthquake occurrence probabilities are explicitly given for various time frames.
In the seismicity screen there are two options to apply the modified Gutenberg-Richter law: the G-R option and the Gridded option.
Source geometry
Regarding their spatial distribution and others factors, sources can be modeled as areas, lines, SSG,Grid, Area Planes, OQRuptures and RectFault.
Attenuation models
Attenuation models (also called Ground Motion Prediction Models, or GMPM) relate, in probabilistic terms, the earthquake characteristics (e.g., magnitude, hypocentral location), and the site location relative to the source, with the intensities produced at the site by the earthquake.
CRISIS admits three families of GMPM: Attenuation tables furnished by the user, built-in parametric models, and generalized attenuation models. These possibilities give CRISIS great flexibility to perform the hazard computations.
Spatial integration procedure
CRISIS operates with a dynamic integration procedure which allows fast computation of hazard in extended areas.