Assessment of activity rates for seismic source zones

This report describes the basis on which magnitude-frequency statistics have been calculated for seismic source zones (SSZs) within the SHARE project conducted for the European Union under the 7th Framework Project Grant Agreement no. 226967. It also serves as a user guide and manual for operating the program Attic Ivy (current version 1.2 as of July 2011). This software was developed within the SHARE project, and is distributable amongst project partners. It is written in FORTRAN and designed to run under MS-DOS (or at a Windows command prompt) but has also been tested under UNIX. The program name is an anagram of "activity". Part of the program is based on code written by R.R. Youngs circa 1992, and made available to SHARE by kind permission for use within the project. The original code has been simplified, and in some places modified, but some legacy features have been retained in the code that are not actually utilised. A companion report will be issued detailing the decisions made in actually computing activity rates for Europe in the SHARE project, and listing the results.