External vs. internal forcing mechanisms in generating maar volcanoes

• Applicant: Professor Dr. Hans-Ulrich Schmincke (†)
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2011 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 200961086

Maars are generally thought to result from magma-water interaction. This project aims at testing the hypothesis that expansion of exsolving CO2 is a major force in ascent and fragmentation of highly silicaundersaturated West Eifel magmas, many laden with mantle fragments, resulting in near-surface pyroclast-water interaction. In the less silica-undersaturated and C02-rich East Eifel magmas, environmental conditions (near-surface, permeable overlain by impermeable sediments) favor phreatomagmatic eruptions, deposits differing drastically from those in West Eifel maars. Excellent exposures will allow a detailed stratigraphic analysis of relevant deposits, single particle analysis including X-ray microtomography, scanning electron microscopy, XRF, LA-ICP-MS and electron microprobe. The geochemical and volcanological contrasts between East and West Eifel will allow a thorough evaluation of external versus internal forcing factors triggering and sustaining highly explosive eruptions that generate maars on one hand and unequivocal glass-rich phreatomagmatic deposits on the other. The results will aid assessing volcanic hazards from explosive eruptions.

• DFG Programme: Research Grants