New research results and a new digital map of the West Eifel Volcanic Field

Within a funded project of the UNESCO Global Geopark Vulkaneifel, the Quaternary West Eifel Volcanic Field (WEVF) was comprehensively re-mapped to create a digital geological map. Compared to earlier maps created by von Dechen (1:80,000), Rahm (1:25,000), and Büchel (1:50,000), the new mapping benefits from high-resolution lidar data, enabling the creation of detailed 3D terrain models. This intensive remapping campaign in 2022-2025 has led to an increase in the number of recognized volcanoes, especially of old maars. Notably, three of these maars are filled with basalts, as relicts of lava lakes. Many large scoria cones exhibit an initial maar phase, with their craters filled by scoria, agglutinates, dykes, plugs, and small lava lakes. Most of the scoria cones have produced lava flows. Tuff-ring volcanoes, rich in juvenile clasts, exhibit palagonitization – evidence of intense magma-water interaction. Additionally, a new volcano type has been identified that generated large deposits of phreato-strombolian tephra. Moreover, quarrying has revealed distinct tensile fault systems along the marginal rims of scoria cones with initial maar phases. These extensional fault structures likely collapsed progressively in the transition zone between the initial maar crater and the diatreme, as a result of the growth of the maar-diatreme volcanoes.