Discovered 5121 km below the surface of the earth an inner core. This discovery was based on observations of the reflection and refraction of seismic waves generated by deep focus earthquakes. From Lehmann's discovery of the earth's inner core have come current ideas on th e origin of the earth's magnetic field described by Professor Leon Knopoff, UCLA.

"The inner core of the earth is now thought to be a solid precipitate of the molten iron/nickel outer core. One popular model has it that the condensation of the inner core is the heat source for driving convective motions in the outer core and hence is a mechanism for generating the earth' magnetic field." --- Leon Knopoff, 1996.

Some Important Publications

" P' ", Union Geodesique at Geophysique Internationale, Serie A, Travaux Scientifiques 14: 87 (1936).

"Velocities of Longitudinal Waves in the Upper Part of the Earth's Mantle", Annales de Geophysique 15: 93 (1959).

"The Travel Times of the Longitudinal Waves of the Logan and Blanca Atomic Explosions and Their Velocities in the Upper Mantle", Bulletin of the Seismological Society of America 52: 519 (1962).

Honors

The Lehmann Medal, instituted by the American Geophysical Union in 1997, is to be awarded in recognition of outstanding research on the structure, composition, and dynamics of the Earth's mantle and core. This medal is the first AGU honor to be named for a woman, and the first to be named for a scientist who worked outside the United States. [eos1997mc]

Jobs/Positions

1925 Royal Danish Geodetic Institute

1928-53 Chief of the Seismological Department of the Royal Danish Geodetic Institute

Education

Attended the first co-educational school in Denmark founded by Hanna Adler, aunt of Niels Bohr.

University of Copenhagen 1907-10
M.S. (mathematics) University of Copenhagen 1920
M.S. (geodesy) University of Copenhagen 1928

References

[bssa1994bb], [1 CLH], [1S N20], [27 LDO], [eos1997mc], [bmfrs1997bb]

Denmark's only seismologist for two decades.

Niles Groes, her nephew , wrote:

"I remember Inge one Sunday in her beloved garden ...with a big table filled with cardboard oatmeal boxes. In the boxes were cardboard cards with information on earthquakes and the times for these and the times for their registration all over the world. This was before computer processing was available, but the system was the same. With her cardboard cards and her oatmeal boxes, Inge registered the velocity of propagation of the earthquakes to all parts of the globe. By means of this information, she deduced new theories of the inner parts of the Earth. ...

"It was not easy for a woman to make her way into the mathematical and scientific establishment in the first half of the twentieth century. As she said, `You should know how many incompetent men I had to compete with - in vain.' "
---- Niels Groes [bssa1994bb]

Reminiscences of Inge Lehmann by Lady Jeffreys.

Recommended Reading

Field Editor: Professor Leon Knopoff