Alexander A. Gusev (1945 - 2018)

Alexander A. Gusev, the head of the Seismology Laboratory at the Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences, passed away on September 21, 2018. He was a wonderful person, an outstanding seismologist, and an exceptional leader, known for his extensive knowledge, pedagogical talent, and the ability to captivate others with his ideas.

Born 5 February 1945, Alexander A. Gusev grew up in Moscow. In 1967 he graduated from the Department of Physics of the Moscow State University and travelled to Kamchatka, which would become the focus of his professional interests. A. A. Gusev's scientific career began at the Pacific Seismological Expedition of the Institute of Physics of the Earth of the Academy of Sciences of the USSR. He joined the post-graduate at IPE in 1969 and transferred to the Institute of Volcanology and Seismology of Far Eastern Scientific Center of the Academy of Sciences of the USSR (now Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences). In 1978, he defended his candidate of science thesis "Numeric detection of hypocenters of close-range earthquakes (example of Kamchatka)," and in 1993 he presented his doctoral dissertation "Properties and origins of short-period emission of earthquake source."

n 2002, a group of researchers including A. A. Gusev was honored with a national award in science and technology of the Russian Federation for the development of a set of seismic zoning maps of Russia. In the last ten years A. A. Gusev did extensive work on the next generation of such maps.

Among A. A. Gusev's main research areas were the earthquake source and its tectonophysical nature; fractal properties of seismic and volcanic processes, signals, and fields; engineer seismology; absorption and dispersion of seismic waves; precursor detection. In all of these areas of scientific research he received fundamental results, widely known and acclaimed in Russia and in the international scientific community. Numerous techniques and numeric methods developed by A. A. Gusev are actively used at the Kamchatka branch of the Geophysical Survey of the Russian Academy of Sciences. As early as 1978, A. A. Gusev was active in digitizing the card earthquake catalogue of Kamchatka. He visited the Institute of Physics of the Earth often, to participate in seminars and conferences and to meet with colleagues. His presentations were always thoughtful and generated a lot of interest in the audience.

A. A. Gusev received recognition and esteem nationally and in the international seismological community. He acted as convener at international meetings. His invited talks captivated his audiences. His opinions were appreciated by the world's leading seismologists. He was one of the greatest seismologists not only in Russia but also over the world. His studies on the theory of random wave-fields generated by earthquake sources and on simulation techniques of strong ground motions have made remarkable impacts.

A. A. Gusev spent a lot of time working with students. He prepared five candidates of science (PhD). He generously shared his knowledge, experience and ideas, the stock of which has never dried up.

Alexander Gusev was extremely active and productive in his work till the end. We lost a person of such scale that is rarely to be seen. His significance to modern seismology is hard to overestimate, and this loss is irretrievable. A warm memory of him will always be in the hearts of his collaborators, colleagues, and friends.

Alexey Zavyalov, Inst. of Physics of the Earth RAS, Moscow, Russia