Assessment of time–spatial changes of shear wave velocities of flysch formation prone to mass movements by seismic interferometry with the use of ambient noise

• Published in: Landslides 2017-06, Vol.14 (3), p.1225-1233
• Main Authors: Harba, Paulina, Pilecki, Zenon
• Format: Article
• Language: English
• Subjects: Agriculture; Ambient noise; Bedrock; Boreholes; Broadband; Civil Engineering; Earth and Environmental Science; Earth Sciences; Flysch; Geography; Heavy vehicles; Interferometry; Landslides; Landslides & mudslides; Lithology; Moisture content; Natural Hazards; Noise; Profiles; S waves; Seismic activity; Seismic analysis; Seismic profiles; Seismic velocities; Seismometers; Shear; Shear wave velocities; Technical Note; Traffic volume; Velocity; Vibration; Water content; Wave velocity; Weathering
• ISSN: 1612-510X; 1612-5118
• DOI: 10.1007/s10346-016-0779-2

This paper presents the results of monitoring flysch formation shear wave velocities at varying conditions of water content by seismic interferometry. Studies were conducted on a section of the active Just-Tegoborze landslide in the southern region of Poland. The landslide is intersected by the state road no. 75, which has a high traffic density. Measurements of the seismic interferometry were made on the basis of the registration of a local high-frequency noise generated mostly by passing heavy vehicles. Measurements were carried out in three series on January, March and July in 2015. Seismic noise vibration was registered using Güralp CMG-6TD broadband seismometers. One of the seismic profiles was located along a geological engineering cross-section prepared from research boreholes data. One of the main results of the work was the sections of changes of shear wave velocity. The interpreted seismic boundaries made it possible to correlate them with the lithological ones. The trough-like shape of the bedrock boundary may be an effect of weathering processes developed in the zone consisting of weak hieroglyphic beds. It is also supposed to be one of the slip surfaces. The seismic sections of shear wave velocity allowed to analyse velocity variations between three measurement series and to compare them with expected water content in colluvium deposits. The presented results of the study confirmed the utility of seismic interferometry based on ambient noise registration in evaluating the behaviour of landslides in the Carpathian flysch formation.