Methodology for using find_fault.py: Jonathan Griffin 18 August 2009 This script is used to find an event for a given geographic location of the source earthquake. It relies on the Event Selector by Ross Wilson. 1: Identify the maximum and minimum latitude and longitude of the fault that you want to find. For example this may be to find approximate an historical event. 2: Deaggregate some events using the Event Selector near the community you are interested in modelling. Use a large range of possible wave amplitudes, e.g. 0.01 - 15.0 m. The Event Selector will generate a file fault.xy. This file contains that coordinates of all the events found by the Event Selector 3: Edit find_fault.py to: Specify the max/min latitude and longitude of the earthquake you are trying to approximate. Specify the search tolerance, in degrees, defining what you consider close enough to the search coordinates. Specify the directory that fault.xy is located in. Output will be a file called possible_quakes.txt in the same directory. 4: Run find_fault.py 5: A list of earthqaukes that fit the search parameters will be produced in possible_quakes.txt. Use this list to then look back through the list in the event selector to find events of the right magnitude and/or slip. 6: To visually check the results, change the extension of fault.xy to fault.txt then add into an ArcMap session. Display xy data, then go into Properties -> Definition Query, where you can define a query based on quake_ID to display the fault data for the possible events. This allows you to check that the fault covers the area you are interested.