This study introduces a simplified analytical method to extract shear wave velocity profiles from seismic waves evoked by explosives, providing a time-efficient solution to the conventional Multichannel Analysis of Surface Waves (MASW) method. Controlled ammonium nitrate emulsion explosions were used at five research sites throughout Thailand with different geological conditions to capture ground motion data through a 16-geophone array during field investigations. This direct analysis evaluates surface wave arrival times in real-time while implementing elastic theory-derived empirical factors for analysis. The proposed method delivers results that match MASW-derived profiles yet require fewer complex procedures and shows Vs30 variations from 4.43 to 38.33%. The simplified method delivered the most accurate results in areas displaying gradual soil property transitions and showed reduced precision when dealing with abrupt soil type or mechanical property shifts. The new method transforms petroleum exploration seismic data into geotechnical applications by delivering dependable shear wave velocity profiles with lower complexity and using fewer resources. It is specifically valuable for limited-budget engineering projects or difficult-to-access locations.

Infrastructure development into peat necessitates geotechnical engineers to find a better profiling method. The conventional profiling carried out by either a localized peat augering or a borehole drilling is often subjective, lacking of details, time consuming and high cost. This paper presents results and analysis of in-situ tests that combines Electrical Resistivity Tomography (ERT) and Multichannel Analysis of Surface Wave (MASW) methods. The results show that ERT method is a good tool for delineating the boundary between peat and underlying mineral soil using their large contrast in electrical resistivity values. The ERT enables the peat thickness to be determined accurately, but lacks of information regarding peat mechanical properties. On the other hand, the MASW provides a lower contrast between the peat and the mineral soil layers compared to the ERT, but it can provide the mechanical properties of the two layers based on shear wave velocity measurements. Hence, the combination of these two methods were found to be improving the peat profiling for engineering application. The results correlate well with the existing peat auger and borehole records in the study area. The combined ERT and MASW methods is recommended to be practically used by engineers as the current best solution for peat profiling.

Subsurface processes significantly influence surface dynamics in permafrost regions, necessitating utilizing diverse geophysical methods to reliably constrain permafrost characteristics. This research uses multiple geophysical techniques to explore the spatial variability of permafrost in undisturbed tundra and its degradation in disturbed tundra in Utqia & gdot;vik, Alaska. Here, we integrate multiple quantitative techniques, including multichannel analysis of surface waves (MASW), electrical resistivity tomography (ERT), and ground temperature sensing, to study heterogeneity in permafrost's geophysical characteristics. MASW results reveal active layer shear wave velocities (Vs) between 240 and 370 m/s, and permafrost Vs between 450 and 1,700 m/s, typically showing a low-high-low velocity pattern. Additionally, we find an inverse relationship between in situ Vs and ground temperature measurements. The Vs profiles along with electrical resistivity profiles reveal cryostructures such as cryopeg and ice-rich zones in the permafrost layer. The integrated results of MASW and ERT provide valuable information for characterizing permafrost heterogeneity and cryostructure. Corroboration of these geophysical observations with permafrost core samples' stratigraphies and salinity measurements further validates these findings. This combination of geophysical and temperature sensing methods along with permafrost core sampling confirms a robust approach for assessing permafrost's spatial variability in coastal environments. Our results also indicate that civil infrastructure systems such as gravel roads and pile foundations affect permafrost by thickening the active layer, lowering the Vs, and reducing heterogeneity. We show how the resulting Vs profiles can be used to estimate key parameters for designing buildings in permafrost regions and maintaining existing infrastructure in polar regions.