Detection of Landslide Direction Based On HVNR Method

Landslide is a destructive phenomenon that causes great damage hence, it is important to reduce these losses by its recognition. Therefore, in this study it is tried to find landslide directivity in a village in Golestan Province named Narges Chal in North of Iran by HVNR method. to achieve this goal, analysis of spectral ratios of horizontal to vertical azimuthal variations of ambient noise (HVNR) recorded by the portable seismometers were accomplished to get information about the directional resonance phenomena. Afterwards, site response directivity by recorded noise analysis was investigated and the results were compared to geological features. For this purpose, four broadband seismometers were used, which were deployed linearly in various directions to monitor landslide properly. The results of HVNR were compared to Geotechnical drilling data that were consistent with the obtained results. The results proved that techniques based on spectral analysis of horizontal to vertical ratios can be useful to check the site effect directional features. it is noticed that there is a prevailing orientation approximately N-S (approximately 0 to 30).The conducted survey showed that this directivity is in the general direction of fractures and faults in the region and also topography dip.