Earth's core discovered by seismology
Núcleo terrestre descubierto por sismología
- Date
- 1906 / 1914 / 1936 · confidence high
- Place
- Copenhagen, Denmark (Inge Lehmann)
- Credited to
- Richard Oldham (core, 1906), Beno Gutenberg (mantle-core boundary at 2900 km, 1914), Inge Lehmann (solid inner core, 1936)
- People
- 👤 Beno Gutenberg1889–1960👤 Inge Lehmann1888–1993👤 Richard Dixon Oldham1858–1936
- Field
- Cosmos & Earth
What was discovered
Oldham detected a shadow zone in seismic waves revealing a core; Gutenberg fixed its depth; Lehmann discovered a solid inner core within it. The Earth turned out to have a concentric structure with an iron heart.
Coordinates of Copenhagen, where Lehmann published her paper 'P'' in 1936. Lehmann was one of the few women in geophysics of her time.
What it led to
- Model of a differentiated Earth (crust, mantle, core)
- Dynamo theory of the magnetic field
- Seismic tomography and the PREM model (1981)
Built on
- Identification of P, S and surface waves (Assam earthquake)1899-1900
- Galitzin electromagnetic seismograph1906
- Milne seismograph
- Mean density of the Earth (Cavendish, 1798)
Made possible
- Jeffreys-Bullen seismological travel-time tables1935-1940
- Global seismology
- Layered models of the Earth