Refining Moho Depth Estimates from Receiver Functions, introducing variable Weights for P-to-S converted Phases

Accurate determination of the Moho depth and seismic velocities is essential for understanding the Earth's crustal structure and geodynamic processes. A widely used approach for estimating Moho depth is the H-k stacking method. H-k stacking makes use of receiver functions and a grid search to identify which values of Moho depth and crustal VP/VS ratio are able to best reproduce arrival times of P-to-S converted phases, recorded in the Receiver Functions. Due to the crustal attenuation and local scattering, multiple converted P-to-S phases, namely PpPs and PsPs+PpSs, generally display lower amplitude with respect to P-to-S phase. To fully take into account this observation, the different P-to-S converted phases are given different importance (i.e. different weights) during the H-k stacking. However, such assumption can introduce bias due to the user-defined weights assigned to the different phase arrival times.To address this limitation, we propose a novel algorithm that extends the traditional H-k stacking approach by introducing two additional dimensions: variable weights for the phase arrival times. This innovation enables us to compute H-k grids using a range of weight configurations and evaluate their probability. The optimal grid is selected based on its probability, thus we reduce the influence of subjective weight assignments.By incorporating variable weights into H-k stacking, our approach aims to reduce bias and improve the robustness of Moho depth estimates. With this enhanced method we hope to contribute to a more precise picture of the Earth's crust and a better understanding of geodynamic processes.