Professor László Cserepes
1952-2002

A few days before Christmas Dr László Cserepes - professor of the Department of Geophysics at the Loránd Eötvös University - died after a prolonged and painful disease.
He was born in Budapest in 1952. After finishing the secondary school he started his studies at the Eötvös University as a student of physics. After the fourth semester he switched to geophysics and obtained his diploma in 1975. He also graduated from physics in 1978. His school achievements were always excellent. Since 1975 he worked at the Department of Geophysics. In 1986 he was promoted to assistant professor, in 1996 to associate professor and, finally, in 1999 he was appointed to full professor.
From the very beginning the major topic of his research has been thermal convection, the global circulation in the Earth’s mantle. A successful research in this frontier subject requires international cooperation Professor Cserepes had established contacts with several foreign institutions. From 1984 he was invited eight times to carry out researches in France (Tolouse, Paris), in Germany (Mainz, Göttingen) and in the United States of America (Minneapolis, MN). The Minneapolis University has already invited him as a guest professor for the fall semester of 2003.
His research concerning the mantle convection was based on the hydrodynamic modelling of the phenomena with the help of powerful computers. His researches culminated in the realization of three fundamental conclusions which significantly helped the further improvements of the theory of mantle convection.
In the early 1980s he proved that the rigidity of the lithospheric plates was a natural consequence of the interaction between the convective circulation and the rheological behaviour of the lithospheric material. This interaction is of prime importance for the existence of the plates. László Cserepes published these results in 1982, and since then the improved mantle convection models were based on this result.
Another major achievement in the early 1990s was the analysis of the 3D circulation patterns in the mantle. He proved that the upwelling mantle material formed columnar shaped cells which were rooted in the deep mantle and at the Earth’s surface they are manifested as hot spots. This result turned out to be a fundamental feature of mantle convection. His third major result was achieved during the last few years, in cooperation with an American scientist. They proved that mantle convection was layered due to a phase change of the material along a boundary layer in the depth of 660 km. They also pointed out that the upwelling columns of the mantle convection were rooted in three different depth levels: within the 660 km boundary layer, right below the boundary layer and in the very bottom of the mantle. Their results were published in 2000, creating world wide appreciation.
László Cserepes also studied other hydrodynamical aspects of geophysics. A fundamental field of research - which brought excellent results during the past few years - is the origin the Earth’s magnetic field as a consequence of the convection within the Earth’s outer core.
It is also to be mentioned that László Cserepes worked almost a decade in the Space Research Group of the Department of Geophysics. His main task was basic physical research and his results dealt with the nature of the very low frequency electromagnetic waves in the magnetosphere.
He was not only an outstanding scientist but a talented teacher, beloved by his students. He disseminated his knowledge during regular and special courses for the undergraduates and post-graduates, and as a consultant of many diploma and PhD theses. While he was in Göttingen he also gave lectures at the university for doctoral candidates in physics and geophysics. He had a fundamental role in the establishment of the former curriculum of the students of geophysics, in the reform of this curriculum due to the integration of universities and initiation of credit system in the higher education, and also in the PhD School of the Eötvös University.
His most characteristics qualities were his devotion to science, his helpfulness and the gentle love with which he found his way to our hearts. We were frightened by the fatal disease which suddenly attacked him, but together with him we believed in his recreation. Unfortunately, we were wrong.
Our dearest colleague and friend! Farewell now! On behalf of the Eötvös Loránd University, the Faculty of Science, the Rector and the Dean, your colleagues and students: God bless you, may you rest in peace!

January 2003, Budapest

Ferenc Horváth