Leyes de atenuación de Ia intensidad macrosísmica en colombia.

In order to establish the regional model of attenuation of macroseismic intensity with distance in the Colombian territory, the isoseismal maps of thirty four strong earthquakes were analysed in this paper. Using some teorical models of attenuation and the macroseismic focal depth we chose three different intervals (h ≤ 20km, h ≤ 60 km and h > 60 km). From here the following three attenuation relations were obtained: Ii=I0 -0.019(x-15)-0.76 ln(x-15), con σ² =0.08; para h≤20km I =(2.3mb - 6.8)1.lx-0.06 e-0.001x, con σ² =0.26; para h≤60km I = I01.26e-0.004x, con r² =0.80; para h>60km For superficial earthquakes, the geometrical spreading coefficient its more important than the coefficient of physical absorption. [ABSTRACT FROM AUTHOR]