Fieldwork among other areas in:

• Antarctica (1984, 1990/1991)
  
  
• South America (from 1986 to 2012),
  
  
• Central America (1989, 1994, 2002-2006)
  
  
• Kamchatka (1996)
  
  
• China (2008-2016) 

• Assoc.-Editor "Terra Nova" (2006 - )
  
  
• Editor "J. Petrol" (2007 - )

• Editor (with with M. Štemprok) "Evolution of Variscan (Hercynian) and Comparable Paleozoic Orogenic Belts" (International Journal of Earth Sciences, 84, 1995) 

• Editor (with Jaillard E, Hérail G und Monfret T, 2002) Andean Geodynamics: Main Issues and Contributions from the 4th ISAG, Göttingen. Tectonophysics 345: 1-15

Research Interests

• Evolution of magmatic systems : from crystals to orogenic scale
  
  
• Magmatism at convergent plate boundaries (Kamchatka, Central America, Andes) Continental rift magmatism and flood basalts (Europe, Antarctica)
  
  
• Interaction between tectonic and magmatic processes in orogenic belts
  
  
• Physical Volcanology

Research Projects

Transcrustal magma systems: Igneous phenocrysts as archive for pre-eruptive conditions and magma system evolution
Several projects have beenconducted on volcanoes in Kamchatka, Central Andes, Canary Islands, Italy, and Germany. Mineral zonations are being analysed with electron microprobe and laser-ablation ICPMS in order to reconstruct the changes in composition of magmas just prior to their eruption. Temporal scales considered range from years to decades and a few thousands of years. 

Residence times and long-term evolution of magma systems
The long-term evolution of magma systems is studied by analysing and dating volcanic products throughout the life-time of selected volcanoes. P-, T-, and f_O2-conditions are reconstructed through time to determine the depth and conditions of magma storage.  Temporal scales range from a few thousand to several hundreds of thousand years. Different methods are applied to gain direct time information on crystal residence and magma differentiation times (Central Andes, Reunion Island, Italy, Germany). Based on these data we reconstruct the assembly and storage of magma reservoirs and document the volume-time-compositional evolution of magma systems through time.

Time-space variation in magma composition during the evolution of convergent plate settings
Subduction zones change their lower plate geometry, convergence rates and angles and upper plate thickness, composition and stress through time. By analysing magmatic products at convergent margins over time (millions to tens of millions of years) and space (hundreds of km along or across arc) we can reconstruct the interplay between these parameters and magma composition in Kamchatka, Central America and the Central Andes. 

Interplay between tectonics, climate, geomorphology and magmatism in the Central Andes
Shortening and crustal thickening and surface uplift in the Central Andes in Cenozoic times is linked to the composition and evolution of magmas that traverse this thickening crust. Uplift and erosion results in geomorphological changes that are punctuated by volcanic events. On the other hand, volcanic rocks serve as important markers of this geomorphological change that is driven by tectonic and climatic forcings. We study this complex interplay in the region of the Atacama Desert at the western margin of the Central Andes in southern Peru and northern Chile. 

Trace element and parent-daughter isotope fractionation during ultra-high-pressure metamorphic dehydration
Subduction of basalts to mantle depth results in ultra-high-pressure (UHP) dehydration that has a potential to change incompatible trace element as well as parent-daughter elements for important isotope systems. In this project, we study elemental transport and fractionation in UHP veins from Dabie-Shan.

 Göttingen, January, 2019