Seismology: a Timeline of Developments
| Year | Instruments and Networks | Earthquakes and Scales | Waves Theory and Earth’s Interior |
|---|---|---|---|
| 132 | Caeng Heng (China) instrument to detect direction | ||
| 1660 | Hooke identifies elasticity of materials | ||
| 1703 | Jean de la Haute Feuille (France) seismoscope design | ||
| 1751 | Pendulum device – Bina (Ital.) | ||
| 1755 | Lisbon (Portugal) Earthquake | ||
| 1759 | Earthquake focus location from deformation – Mitchell | ||
| 1783 | Calabrian Earthquake: detailed documentation by commission | ||
| 1799 | Cavendish calculates mean density of the Earth | ||
| 1839 | Poisson identifies pressure and shear waves | ||
| 1844 | Inverted pendulum – Forbes (Scot.) | ||
| 1846 | Noggerath simple isoseismal map for the Rhineland Earthquake | Mallet proposes earthquakes cause transient waves of elastic compression | |
| 1855 | Visp Earthquake (Switz.) | Airy’s crustal root isostacy model | |
| 1856 | Vertical & horizontal motions with springs or “seismografo electtro-magnetico – Palmieri (Ital.) | ||
| 1857 | Neopolitian Earthquake: studied by Mallet – map of isoseismal lines; Volver and Petermann map of seismic intensity for Visp Earthquake | Pratt thick crust model | |
| 1859 | Map of worldwide distribution of earthquakes – Mallet | ||
| 1862 | Mallet proposes elastic wave model | ||
| 1873 | Horizontal pendulum – Zollner (Germ.) | ||
| 1874 | DeRossi (Ital.) proposed intensity scale | ||
| 1875 | Multiple pendulums with different lengths; movements traced on paper – Cecchi (Ital.) | ||
| 1881 | Seismograph that records different components of motion – Gray and Ewing (Japan); Seismological Society of Japan founded | Forel (Switz.) proposed intensity scale | Fisher: textbook on geophysics, supports thin crust and isostacy |
| 1887 | Rayleigh identifies Rayleigh waves | ||
| 1888 | DeRossi & Forel Intensity scale | Schmidt recognizes that seismic waves would have curved paths due to increased velocity with depth | |
| 1889 | Seismography improvements – Rebeur-Paschwitz (Germ.) | Tokyo Earthquake detected in Germany by Rebeur-Paschwitz | |
| 1891 | Koto observed large fault scarps associated with the Mino-Owari Earthquake | ||
| 1894 | Rebeur-Paschwitz proposed formation of seismic networks | ||
| 1895 | Milne initiates seismic network of 34 stations throughout British Empire | ||
| 1897 | Assam Earthquake: detected in Italy by Oldham | ||
| 1899 | Detection of S and P waves – Oldham | ||
| 1900 | Wiechert seismic network established in German colonies | World seismic maps – Milne and Montessus de Ballore | |
| 1903 | Modern seismograph using reversed pendulum – Wiechert (Germ.) | ||
| 1904 | International Seismology Associate founded | ||
| 1906 | Electrically operated instruments – Galitzin | San Francisco Earthquake – leads to Read’s elastic rebound model | Oldham and Leybenzon detect the existance of the core from S-waves |
| 1909 | Odenbauch (Jesuit) network of 18 seismograph stations completed | Kulpa Valley (Croatia) Earthquake – studied by Mohorovicic | |
| 1910 | Mohorovicic defines the Moho discontinuity | ||
| 1911 | Love identifies Love waves; Oldham, Leybenzon and Jeffreys detect the fluid nature of the core from S-wave shadow | ||
| 1910 | |||
| 1913 | Gutenberg identifies the core-mantle boundary at 2900 km | ||
| 1914 | Barrell detects the asthenosphere | ||
| 1920 | Turner and Wadati recognize earthquakes extend 100s km in depth | ||
| 1925 | Jesuit Seismological Association founded | ||
| 1926 | Chile Earthquakes studied by Guttenberg | Guttenberg suggests asthenosphere is zone of slower velocity | |
| 1929 | Buller (New Zealand) Earthquake studied by Lehmann | Lehmann proposed that the inner core is solid | |
| 1935 | Richter Scale | Wadati recognizes inclined zone of earthqaukes | |
| 1936 | Lehmann proposed that the inner core is solid | ||
| 1954 | Jesuit network detected Bikini A-bomb test | Benioff independently recognizes Wadati zones | |
| 1958 | Gorshkov identifies fluid nature of the asthenosphere | ||
| 1963 | Nuclear Test Ban Treaty: leads to US funding of seismograph network |