'Adam Dziewoński' (
★
1936, in
Ukraine, formerly
Poland) is a Polish-American
geophysicist who has made seminal contributions to the determination of the large-scale structure of the
Earth's interior and the nature of
earthquakes using
seismological methods. He is the Frank B. Baird, Jr. Professor of Science at
Harvard University.
Life and main scientific contributions
After having earned a Masters from the
University of Warsaw, Poland (1960), and a Doctor of Technical Sciences from the Academy of Mines and Metallurgy, Cracow, Poland (1965) Dziewonski taught at the
University of Texas, Austin for several years before settling at Harvard.
In the 1960s and 1970s, Dziewonski and his collaborators laid the foundation to the understanding of
tectonic plate motions by exploring
convection currents in the
Earth's mantle with radial maps of seismic property variations, based on measurements of
seismic waves. These studies led to the development of the Preliminary Reference Earth Model (PREM) in collaboration with
Don Anderson; PREM establishes an accurate radial model of the Earth for seismic velocities,
attenuation, and
density.
Since the 1980s he has led two original and powerful research efforts. He has extended the radial models to be fully three-dimensional, along the way mapping and interpreting four "Grand" structures. The four include two regions of higher-than-average wavespeed, inferred to be cold and sinking mantle, one under the western edge of the Americas and the other under southern Eurasia. The two other features are slower-than-average wavespeed, inferred to be hot and rising, under the middle of the Pacific Ocean and Africa.
His other research direction has determined the orientation and
magnitude of the deformation for most of the significant earthquakes that have been well-recorded. These results are known as the Harvard CMTs (centroid moment tensor solutions) and are continued today at
Lamont-Doherty Earth Observatory by Goran Ekstrom as the Global CMT Project.
Dziewonski has received numerous honours and awards for his scientific achievements, among them the Gold Medal of
Ettore Majorana Foundation and Centre for Scientific Culture (1999), Medal of the Seismological Society of America (2000), the
Crafoord Prize of
the Royal Swedish Academy of Sciences (1998), and the Bowie Medal of the
American Geophysical Union (2002). He is also a member of the
National Academy of Science.
Important publication
★ A. M. Dziewonski, D. L. Anderson: Preliminary reference Earth model. ''Physics of the Earth and Planetary Interiors 25, S.297–356 (1981)
External links
★
Dziewonski's webpage at Harvard
★
Global Centroid Moment Tensor project
★
Citation upon receiving Bowie Medal