Keith Edward Bullen
Keith Edward Bullen ( born June 29, 1906 in Auckland, † September 23, 1976 ) was a New Zealand mathematician, geophysicist and seismologist.
Life
His academic and student training enjoyed bulls near his home town of Auckland. In 1922 he finished the Auckland Grammar School with an award for math and science along with the intake at the university. In the following years he graduated in the field of mathematics, on which he also won other awards. In 1928 he was a lecturer in mathematics at Auckland University College.
Bulls left in 1931, the University temporarily, to do his doctorate at St John 's College at Cambridge University, then returned to Auckland but again back to his teaching resume. In 1940 he moved to Australia, where he worked as a lecturer at the University of Melbourne. Five years later he became Professor of Applied Mathematics at the University of Sydney, where he remained until his retirement in 1971.
Keith Bullen married in 1935 Florence Mary Pressley. Together they had two children, John ( * 1936 in Auckland ) and Anne ( born 1943 in Melbourne). Bulls died of a heart attack at the age of 70 years.
Research
During his years at Cambridge was a student of Harold Jeffreys cops who worked at that time on a revision of the terms of earthquake waves that were still affected by errors of up to 20 seconds. One of the first publications Bullens (along with Jeffreys ) was a Nature article about the corrections of the P-wave durations. Upon his return to New Zealand bulls kept on active contact with Jeffreys and ended in Auckland his doctoral thesis.
1940 published both the so-called Jeffreys - Bullen tables - an overview of run times for different Seismogrammphasen, which was the basis for the understanding of the inner earth structure over several decades. This the first time there was a defined layer model of the Earth.
Bulls, however, published in the episode further their own studies and tables to further reflected seismic waves. Subsequent work dealt with the structure of the Earth, calculations of distances in seismology and the change in density within the earth with increasing depth. At the latest with the release of the latter topic in the 50s Bulls won worldwide recognition and became one of the leading geophysicists of his time.
Bulls continued to refine the earth model and progressed to the conclusion that the Earth's mantle and the Earth's core must have chemically different. He also postulated the occurrence of an extremely large density gradient in the lowest 200 km of the mantle, the zone that is known as D "layer now. Bullens More publications also deal with the state of the terrestrial planets. , The density distribution in the soil, however, remained the dominant field of Bullens, which he discussed in his recent 1975 book The earth's density.
Bullens life's work includes approximately 290 publications, some of which have caused significant influences on the geophysics. His international recognition came in a variety of offices to express: he was president of the International Association of Seismology and Physics of the Earth 's Interior and Vice - President of the International Union of Geodesy and Geophysics and the International Scientific Committee for Antarctic Research and other working groups and committees that dealt with geophysics and seismology.
The energy, put the cops in his work, was described by his former PhD supervisor Harold Jeffreys phenomenal. He pointed to congresses and conferences always willing to talk with interested regardless of age. Keith Bullens achievements and accomplishments have been recognized with a number of honors and awards.
Writings (selection )
- Tables for converting geographic into geocentric angular distances. Isle of Wight 1938
- An introduction to the theory of mechanics. Sydney 1949
- An introduction to the theory of seismology. Cambridge 1952
- Seismology. London 1954
- The interior of the earth. San Fransicso 1955
- The Earth 's density. London 1975