The lithosphere-asthenosphere boundary (LAB) marks the base of the Earth’s outer layer where heat is transferred primarily by conduction as compared to prevailing convective heat transport below. Spatial variations in LAB depth reveal the differential evolution of tectonic systems (e.g., rifts and orogens), thus enabling a better understanding of geodynamic processes. Further, the topography of the LAB exerts control on the coupling of the lithosphere to asthenospheric flow, modulating the distribution of present-day stresses and active deformation of the tectonic plates. We have derived global depth variations of the LAB from temperature-converted shear-wave tomography models assuming that the threshold temperature between conduction and mantle convection is 1300 °C. Shear-wave velocity in the mantle is controlled by both in situ pressure-temperature conditions and mineralogical rock composition. Therefore, our velocity-to-temperature conversion builds on a framework of rock physical properties generated through a Gibbs free energy minimization to determine thermodynamically stable phase and mineral assemblages throughout upper mantle pressure and temperature conditions. In this data publication, we provide thermal LAB depths corresponding to one European-scale and three global-scale tomography models. The data release includes (i) a data description file with information on the input tomographic models, the conversion method and spatial variations in LAB depth (illustrated); and (ii) four data files with LAB depth values spatially sampled according to the input tomography models.
This data set contains hypocentral parameters (latitude, longitude, depth, local magnitude, and origin time) for 13566 aftershocks of the 2019, M6.4 Durrës, Albania earthquake. Aftershocks were recorded with a 30 station local network, which started operation about two weeks after the and registered for about nine months. Event detections were produced with machine-learning-based tools. Aftershocks were located with a newly derived 1D velocity model with station corrections. Final relocation was done with the double-difference algorithm including cross correlation derived differential travel times. Local magnitudes range from Ml −1.8 to 4.6 with a magnitude of completeness of Mc ≈ 1.