application of d-patv method to determine the first arrival time in seismic refraction tomography

The study utilized seismic refraction tomography to accurately visualize underground layers, employing three arrival time calculation methods: expert user determination, hatherly method, and d-pavt method. the aim was to explore automatic first-breaks picking determination methods for scenarios with limited data or inexperienced researchers. the d-patv method has yielded satisfactory results when compared to the hatherley method, often displaying the closest resemblance to the expert user's output. in urban seismic refraction data acquisition, noise is inevitable. therefore, in the proposed method for first-breaks picking, we first smooth the signal with the powerful d-patv method and then determine the start of the event with the derivative of the results. it should be noted that since this method is based on derivation, it can only be used in case of resources with minimum phase.