Lunchtalk Crustal structure of The Netherlands from waveform-fitting of receiver functions Stephen Akinremi

This study presents the first crustal thickness and Vp/Vs estimates for The Netherlands, derived from receiver functions (RF). Using a two-step methodology, we modelled the sedimentary and sub-sedimentary crustal structures with two layers of constant seismic velocities. In the first step, sedimentary layer thickness and Vp/Vs were determined through H-ƙ stacking of high-frequency RFs. This was followed by waveform-fitting of observed RFs with synthetic RFs, enabling constraints on crustal thickness and average sub-sedimentary Vp/Vs. Our findings reveal that the crust reaches thickness of 38 km beneath major structural highs, and characterized as felsic, due to low average Vp/Vs of ~1.68. In sedimentary basins, the crustal thickness is notably thinner ~30 km, reflecting the polyphase deformation history associated with rift basin evolution. Pronounced crustal thinning of 28 km is observed in the Central Netherlands Basin and the Roer Valley Graben. These results provide new insights into the tectonic framework of The Netherlands.

Stephen Akinremi is a PhD candidate on the NWO-DeepNL funded project: “Deep, deeper, deepest NL – Imaging the Dutch crust and upper mantle using multi-geo-observables (DICTUM)”. His current research is focused on modelling the Dutch subsurface (crust and upper mantle) using seismological data in integration with other geophysical observables (e.g., gravity) using a joint inversion method. He has a bachelor’s degree in Applied Geophysics from the Obafemi Awolowo University, Nigeria and obtained a master’s degree at the University of Twente in Geoinformation Science and Earth Observation, specialising in Geophysics and Applied Remote Sensing for Earth Sciences.