Lithospheric Sill Intrusions and Present‐Day Ground Deformation at Rhenish Massif, Central Europe

The Rhenish Massif in Central Europe, which includes the Eifel Volcanic Fields, has shown ongoing ground deformation and signs of possible unrest. A buoyant plume exerting uplift forces at the bottom of the lithosphere was proposed to explain such deformation; the hypothesis of (possibly concurrent) melt accumulation in the crust/lithospheric mantle has not been explored yet. Here, we test deformation models in an elastic half-space considering sources of varying aspect ratio, size and depth. We explore the effects of data coverage, noise and uncertainty on the inferred source parameters. We find that the observed deformation would require melt accumulation in sub-horizontal sill-like structures expanding at the rate of up to similar to 0.045 km3/yr. We discuss feasibility, limitations and possible interpretations of our resulting models and elaborate on further observations which may help constrain the structure of the Rhenish Massif magmatic system.Geodetic observations over the last 20 years recorded small but steady ground deformation over a wide area centered on the Eifel Volcanic Fields, Germany, where volcanism has occurred as recently as 11,000 years ago. Together with geophysical and geochemical evidences of possible ongoing unrest, the observed deformation has renewed interest over the origin of volcanism in the region. The deformation has been tentatively related to a buoyant plume in the asthenosphere. Here, we test whether the deformation may be, at least partially, originating in the lithosphere. We find that deformation data would be consistent with melt intrusions in one or more horizontal lenses located in the lithosphere, but limitations exist due to models simplifications. We discuss feasibility, limitations and possible interpretations of our results, and what additional data may improve our knowledge on the underlying magmatic system.We explore the hypothesis that the ongoing uplift in the Rhenish Massif is (partly) due to melt accumulating in the lithosphereObserved ground deformation would require the intrusion of up to similar to 0.045 km3/yr into one or more horizontal magma lensesWe test different deformation sources and discuss the feasibility, limitations and possible interpretations of the resulting models