Difficulties on Seismic Hazard Assessment for Ibagué because scarcity of data

Abstract

The present paper contains a Probabilistic Seismic Hazard Analysis for the city of Ibagué. A 34.800 km2 area was taken, where the potentially active faults (quaternary ones) are reviewed, and the historic and the instrumental seismicity were analyzed with a cut off magnitude of Ms > 4,0. Subsequently, where the time interval in which the occurrence of earthquakes conform to a Poisson process, to then use different attenuation equations that allow determining the peak ground acceleration in function of several return periods. For a return period of 475 years, accelerations between 275 and 380 gals were estimated. It is commented about deterministic approaches and a final remark about the possibility that Ibagué fault could produce slow, quiet or silent earthquakes