A HYBRID METHOD FOR THE ESTIMATION OF GROUND MOTION IN SEDIMENTARY BASINS - QUANTITATIVE MODELING FOR MEXICO-CITY - COMMENT

Two possible extensions of the commented article are suggested, with t he aim to more efficiently couple the source and path simulation on on e side, and the site-effect simulation on the other: (1) New excitatio n lines, surrounding the sedimentary basin, reduce the necessary size of the 2D finite-difference model of the site. They also better repres ent the 3D nature of the excitation, including the focal-mechanism eff ect. (2) New (2.5D approximate) equations of motion improve the way th e 3D excitation is propagated within the 2D site model. The two sugges ted improvements can help in solving problems when a purely 2D treatme nt is oversimplified, but a true 3D treatment is too expensive.