Seismicity

Appropriate levels of seismicity can trigger landslides. Significant regions of the world are prone to such triggering events. For example, in the Caribbean it is considered that an earthquake on 18 September 1999 measuring 4.7 on the Richter scale, triggered a significant landslide, whilst in parts of Europe and the Far East similar events have promoted links to be made between the required gravitational acceleration required to initiate landslides and local building codes.

Parameterising seismicity is both difficult and complex. CHASM™ uses an empirical guide-line method reported by Charalambus 2003 to estimate the horizontal seismic acceleration to induce instability. The software manual provides an illustration of the link between this resultant acceleration and the required Richter scale trigger for selected examples derived from different countries. A degree of local calibration of this form is required in the use of the resultant acceleration.

Reference:
Charalambus, S 2003 Methodology development for the stability evaluation of natural and man-made slopes against static and seismic loads in a GIS environment. Technical University of Athens, Greece