An Inversion of Rayleigh Waves Dispersion Curves as a Tool to Recognize the Bedrock Depth in Chorzów Stary, Poland

[摘要] Identification of a bedrock beneath soft cover is one of the most important task in engineering geology. The location of boundary-overburden information may be used by investors, builders and municipal authorities to design an infrastructure or land-use plans. In such issues the application of appropriate geophysical methods is useful. However, in urban zones and areas characterized by subsurface soft layer the usage of certain methods (eg.: seismic refraction) is not advisable. The passive method of Refraction Microtremor (ReMi) can fulfill its tasks in the relatively difficult urban environment. The vertical S-wave velocity profiles were carried out as a result of inversion of Rayleigh wave dispersion curves obtained from ReMi method. The change of S-wave velocities allowed to distinguish shallow geological layers in the area of Chorzów Stary. Preliminary measurements allowed to identify the Carboniferous bedrock at a depth of 14 -18 m what has been confirmed by resistivity imaging. Furthermore, unconsolidated deposits are also recognized and the seismic results show a good correlation with the available geological information and resistivity imaging data.

[学科分类] 地质学

[关键词] Ambient seismic noise;ReMi;resistivity imaging;bedrock-overburden boundary;Chorzów Stary;szum sejsmiczny;ReMi;obrazowanie oporności;granica podłoże-nadkład;Chorzów Stary