Seismic intensity zoning and earthquake risk mapping in Iraq

The recently published Iraqi earthquake data file over the period 1905–1984 is used to derive a local I_o-M_sformula. This is then combined with a local intensity attenuation relationship to compile the observed I_o(MM) zoning map for Iraq. Earthquake risk is calculated using the log N (M_s)relation for selected design magnitudes and periods and is mapped as the (%) probability of occurrence using a 0.5 deg latitude/longitude grid system. It is observed that the intensity zones and contour distributions are highly influenced by the presence of large magnitude shocks while risk maps reveal the Tauros seismogenic zone as having a greater risk of occurrence than the Zagros zone. The compiled zoning maps are intended for the use of local practising engineers for earthquake-resistant design procedures that are currently being adopted in the country.