Alfred Kröner (1939–2019)
Alfred Kröner, one of Germany’s most productive and renowned geologist passed away on May 22, 2019. His research on the geologic evolution of the continental crust influenced the work of geoscientist all over the world. Alfred was born in 1939 in Germany. He studied Geology at the University of Clausthal-Zellerfeld, where he received his Vordiplom (BSc equivalent). He continued his studies at the University of Vienna, where he was enrolled in geology and in parallel in music at the Conservatory, playing the violoncello. He fortunately decided to continue his career in geology at the University of Munich, where he earned his Diploma Degree (MSc equivalent) in 1965. Tossing a coin, decided in favor of moving to South Africa for his PhD, rather than India and thus began his regional focus on Archean geology work. He moved to the University of Cape Town, where a PhD degree was awarded to him in 1968. Before continuing in academia, Alfred gained experience as an exploration geologist in South Africa and Namibia. His first academic position was as Senior Research Fellow at the University of Cape Town, where he acted as a director of the Precambrian Research unit between 1974 and 1976. In 1977, he was appointed as Full Professor at the Johannes Gutenberg University of Mainz in Germany. Alfred also spent several years abroad as a guest professor at Stanford University (USA), Australian National University, and at the University of Western Australia in Perth. In Mainz, he maintained a close relationship with the Max-Planck Institute for Geochemistry, where he used the mass-spectrometer facilities to obtain precise zircon ages to understand geodynamic processes with the emphasis on Precambrian rocks. After his retirement at Mainz in 2006, he accepted an invitation from the SHRIMP Center of the Chinese Academy of Geological Sciences (CAGS) in Beijing for a long-term collaborative guest professorship to spend every year 6 months in Beijing. His motivation and enthusiasm for fieldwork made him a globetrotter, because he truly believed in the importance of combining laboratory data and models with empirical observations. Hence, he travelled around the world to collect tons of rock samples that he dated to develop geodynamic models, often the first robust ones for many regions in times when fast measurements of good quality data were still not possible, which further underlines the vast amount of energy and lifetime he invested for improving knowledge on crustal formation processes. Especially his work on the geology of southern Africa, China, Sri Lanka, India and the Central Asian Orogenic Belt gained much interest in the international geology community. In his studies, he always involved local geologist in his project, enhancing their careers. Furthermore, he incorporated his students into his research projects and introduced them to remote fieldwork in exotic places, providing them with unforgettable professional and life experiences. Political barriers or potential obstacles were never a problem for him. He just wanted to bring the samples * J. Elis Hoffmann jeh@zedat.fu-berlin.de