Comparative assessment of surface and body wave methods for shear wave velocity profiling in Almaty basin

Almaty is located near seismically active faults, where periodic earthquakes pose a sig-nificant hazard. Although no large earthquakes have occurred in recent years, historical records indicate past events with substantial casualties. Accurate characterization of dy-namic soil properties is essential for appropriate seismic design, with shear wave velocity (V_s) being the most widely used parameter for site classification. In many practical cases, budget constraints limit site investigations to a single V_s estimation method, potentially introducing methodological bias. This study aims to evaluate and compare the performance of non-invasive surface wave techniques and body wave-based methods in estimating V_s pro-files across multiple sites in Almaty. Multichannel analysis of surface waves (MASW) and ellipticity curve inversion derived from horizontal-to-vertical spectral ratio (HVSR) measure-ments were employed at surface wave techniques. Their results were benchmarked against those obtained from seismic refraction and seismic dilatometer tests (SDMT), the latter being the only invasive method used. Among all techniques, SDMT – based on the true-interval approach – provided direct and high-resolution V_s measurements. However, surface wave methods demonstrated sufficient accuracy, with V_s30 values in good agreement with those from invasive methods. Given their cost-effectiveness and practical applicability, sur-face wave techniques are recommended as reliable alternatives for evaluating dynamic soil properties in urban environments such as Almaty.