Háskóli ÍslandsUniversity of IcelandOlafsdottir, Elin AstaErlingsson, SigurdurBessason, Bjarni2024-06-202024-06-202023-03-28Olafsdottir, E.A., Erlingsson, S. & Bessason, B. (2023). Hybrid non-invasive characterization of soil strata at sites with and without embedded lava rock layers in the South Iceland Seismic Zone. Bull Eng Geol Environ 82, 146. https://doi.org/10.1007/s10064-023-03136-01435-95291435-9537https://hdl.handle.net/20.500.11815/4951The geological setting of Iceland is unusual, with highly jointed rock mass, loose sediments created in glacial outburst floods and eruptions, and layers of lava-rock embedded in or overlying soft sediments. This study aims to assess the feasibility of a composite analysis of dispersion and ellipticity curves for characterization of two of the primary classes of soil sites in the South Iceland Seismic Zone. Specifically, it seeks to develop a cost-effective workflow to identify and characterize sites where a layer of lava-rock is embedded in the sedimentary stratum at shallow depth, along with deep soil site characterization. Microtremor HVSR (horizontal-to-vertical spectral ratio) is found to be efficient to distinguish between sedimentary sites with and without an embedded lava-rock layer. The results further demonstrate the effectiveness of hybrid ellipticity and dispersion curve inversion to characterize soil sites with an embedded layer of lava-rock, which results in a strong velocity reversal with depth. Consistent with previous studies, the hybrid dispersion-ellipticity inversion is also found efficient for characterization of sites with a simpler structure.eninfo:eu-repo/semantics/openAccessShear wave velocitySurface wave analysisRayleigh wave ellipticityVelocity reversalEmbedded lava-rock layersinfo:eu-repo/semantics/articleBulletin of Engineering Geology and the Environment10.1007/s10064-023-03136-0