A dense seismological profile through the Western Carpathians – new data for understanding Earth’s structure, geodynamic evolution and seismicity

Abstract

The tectonic evolution of the Western Carpathians remains a widely debated and polarizing topic. Serving as a crucial link between the Eastern Alps and the Eastern Carpathians, this segment of the orogenic belt formed through the closure of the Alpine Tethys Ocean and subsequent regional shortening. Despite over 150 years of geological investigation and well-documented surface geology, the deep structure of the Western Carpathians continues to be the subject of competing hypotheses. To address these uncertainties, a passive seismic experiment has been initiated across the Western Carpathians, funded by the National Science Centre (Poland) and conducted under the framework of the AdriaArray initiative. Seismic station deployment began in May 2023, with data acquisition planned to continue through 2026. The resulting dataset will benefit a wide range of research focused on local seismicity and the seismic imaging of the crust and upper mantle. The primary objective of the project is to perform Receiver Function analysis to image the lithospheric structure beneath the Western Carpathians. Techniques such as Common Conversion Point (CCP) stacking and Receiver Function inversion will be employed to derive key information about the crust-mantle boundary and lithospheric architecture along the profile. This contribution presents preliminary CCP stacks and a corresponding interpretation of Moho depth. Upon completion of the data collection, further Receiver Function analyses using the full dataset will be carried out, alongside potential
field studies. Combined with existing geological data these results aim to inform the development of a comprehensive model for the tectonic evolution of the Western Carpathians.