History of geophysics

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The historical development of geophysics has been motivated by two factors. One of these is the research curiosity of humankind related to Planet Earth and its several components, its events and its problems. The second one is economical usage of Earth resources (ore deposits, petroleum, water resources, etc.) and Earth-related hazards such as earthquakes, volcanoes, tsunamis, tides, and floods.

Classical and observational period[edit]

In circa 240 BC, Eratosthenes of Cyrene measured the circumference of the Earth, using trigonometry and the angle of the Sun at more than one latitude in Egypt.

There is some information about earthquakes in Aristotle's Meteorology, in Naturalis Historia by Pliny the Elder, and in Strabo's Geographica. Aristotle and Strabo recorded observations on tides.

A natural explanation of volcanoes was first undertaken by the Greek philosopher Empedocles (c. 490-430 B.C.), who considered the world divided into four elemental forces: Earth, Air, Fire and Water. Empedocles maintained volcanoes were manifestation of Elemental Fire. Winds and earthquakes would play a key role in explanations of volcanoes. Lucretius, claimed Mount Etna was completely hollow and the fires of the underground driven by a fierce wind circulating near sea level. Observations by Pliny the Elder noted the presence of earthquakes preceded an eruption. Athanasius Kircher (1602–1680) witnessed eruptions of Mount Etna and Stromboli, then visited the crater of Vesuvius and published his view of an Earth with a central fire connected to numerous others caused by the burning of sulfur, bitumen and coal.

Instrumental and analytical period[edit]

A Galilean thermometer

Arguably the first modern experimental treatise was William Gilbert's De Magnete (1600), in which he deduced that compasses point north because the Earth itself is magnetic. In 1687 Isaac Newton published his Principia, which not only laid the foundations for classical mechanics and gravitation but also explained a variety of geophysical phenomena such as the tides and the precession of the equinox.

Then these experimental and mathematical analyses were applied to several areas of geophysics: Earth’s shape, density, and gravity field (Pierre Bouguer; Alexis Clairaut and Henry Cavendish), Earth’s magnetic field (Alexander von Humboldt, Edmund Halley and Carl Friedrich Gauss), seismology (John Milne and Robert Mallet), and Earth's age, heat and radioactivity (Arthur Holmes and William Thomson, 1st Baron Kelvin).

There are several descriptions and discussions about a philosophical theory of the water cycle by Marcus Vitruvius, Leonardo da Vinci and Bernard Palissy. Pioneers in hydrology include Pierre Perrault, Edme Mariotte and Edmund Halley in studies of such things as rainfall, runoff, drainage area, velocity, river cross-section measurements and discharge. Advances in the 18th century included the Daniel Bernoulli's piezometer and Bernoulli's equation as well as the Pitot tube by Henri Pitot. In the 19th century, groundwater hydrology was furthered by Darcy's law, the Dupuit-Thiem well formula, and the Hagen-Poiseuille equation for flows through pipes. Physical Geography of the Sea, the first textbook of oceanography, was written by Matthew Fontaine Maury in 1855.[1]

The thermoscope, or Galileo thermometer was constructed by Galileo Galilei in 1607. In 1643, Evangelista Torricelli invented the mercury barometer. Blaise Pascal (in 1648) rediscovered that atmospheric pressure decreases with height, and deduced that there is a vacuum above the atmosphere.

20th century[edit]

The 20th century was a revolutionary age for geophysics.

Physics of Earth’s interior and seismology were developed by Emil Wiechert, Beno Gutenberg, Andrija Mohorovičić, Harold Jeffreys, Inge Lehmann, Edward Bullard, Charles Francis Richter, Francis Birch, Frank Press, Hiroo Kanamori and Walter Elsasser.

In the second half of 20th century, plate tectonics theory was developed by several contributors including Alfred Wegener, Maurice Ewing, Robert S. Dietz, Harry Hammond Hess, Hugo Benioff, Walter C. Pitman, III, Frederick Vine, Drummond Matthews, Keith Runcorn, Bryan L. Isacks, Edward Bullard, Xavier Le Pichon, Dan McKenzie, W. Jason Morgan and John Tuzo Wilson.

Advances in physical oceanography occurred in the 20th century. Sea depth by acoustic measurements of was first made in 1914. The German "Meteor" expedition gathered 70,000 ocean depth measurements using an echo sounder, surveying the Mid-Atlantic Ridge between 1925 and 1927. The Great Global Rift was discovered by Maurice Ewing and Bruce Heezen in 1953 while the mountain range under the Arctic was found in 1954 by the Arctic Institute of the USSR. The theory of seafloor spreading was developed in 1960 by Harry Hammond Hess. The Ocean Drilling Program started in 1966. There has been much emphasis on the application of large scale computers to oceanography to allow numerical predictions of ocean conditions and as a part of overall environmental change prediction.

As an international scientific effort between 1957 and 1958, the International Geophysical Year or IGY was one of the most important for scientific activity of all disciplines of geophysics: aurora and airglow, cosmic rays, geomagnetism, gravity, ionospheric physics, longitude and latitude determinations (precision mapping), meteorology, oceanography, seismology and solar activity.

Industrial applications of geophysics were developed by demand of petroleum exploration and recovery in the 1920s. Later, petroleum, mining and groundwater geophysics were improved. Earthquake hazard minimization, soil/site investigations for earthquake prone areas were a new application of geophysical engineering in the 1990s.

Origin of the word[edit]

The word "Geophysik", as far as is known, was first used in 1834 by Julius Fröbel[2][3] He discussed geophysics in letters to his former teacher, Christian Friedrich Schönbein.[4]

The word geophysics appeared in print only a few times between 1834 and the 1880s. An 1848 edition of the encyclopedia Meyers Großes Conversationslexikon included the article "Geophysik", perhaps written by Fröbel.[5] [6][7]

Carl Friedrich Naumann used the term in 1849 in a new context in his Lehrbuch der Geognosie, portraying geophysics as one of three parts of the “geognosy of the whole Earth”, along with geodesy and Abyssologie, the science of the deep Earth. He also discussed a geognosy of the peripheral parts of the Earth: geology of the crust, hydrography, and atmospharologie. Naumann used Geophysik with a more restricted meaning.

The term geophysics appeared sporadically through the 1860s and 1870s in Germany.[7] Adolph Muhry used it in association with meteorology and climatology in 1863. In the 1870s, Georg von Neumayer applied it to the oceans and Ferdinand von Richthofen to the solid Earth. Related terms were used in English, Italian, and probably in other languages. In 1840, John Herschel[8] wrote of terrestrial physics and physical geography. Angelo Secchi, Ernesto Sergent, and Francesco Denza, among other Italians, preferred the term fisica terrestre. Secchi (1879)[9] and Sergent (1868))[10] presented physical terrestrial topics for students. Denza (1882) [11] discussed meteorology specifically as a part of terrestrial physics. In Turkish, the word Arzi Fiziki that means geophysics appeared in 1920s in the name of Kandilli Observatory as "Arzi Fiziki Kandilli Rasathanesi".[12]

The problem of foundation of geophysics as an independent scientific discipline has been discussed by Wilfried Schröder.[13][14] General research into the history of geophysics has been done by the "commission for history of geophysics and cosmical physics" (Bremen) under the direction of Wilfried Schröder, which published the journal Berichte der Geschichte der Geophysik und Kosmische Physik.

See also[edit]

References[edit]

  1. ^ Maury, M. F. (1855). The physical geography of the sea. Harper & Brothers. 
  2. ^ Buntebarth, G. (1981) "Zur Entwicklung des Begriffes Geophysik", Abhandlungen der Braunschwiegischen Wissenschaftlichen Gesellschaft 32, 95-109
  3. ^ Beck, H. (1961) Alexander von Humboldt, 2 Vols (Wiesbaden: Steiner)
  4. ^ Good, G.A., 2000 , The Assembly of Geophysics: Scientific Disciplines as Frameworks of Consensus, Stud. Hist. Phil. Mod. Phys., Vol. 31, No. 3, pp. 259-292.
  5. ^ "Geophysik". Meyers Grosses Conversationslexikon 12. Dresden. 1848. pp. 530ff. 
  6. ^ Kertz, W. (1979) "Die Entwicklung der Geophysik zur eigenstandigen Wissenschaft", Mitteilungen der Gauss-Gesellschaft, No. 16, 41-54.
  7. ^ a b Buntebarth, G. (1981) Zur Entwicklung des Begriffes Geophysik', Abhandlungen der Braunschwiegischen Wissenschaftlichen Gesellschaft 32, 95-109
  8. ^ Herschel, J. (1840) Terrestrial Magnetism', Quarterly Review, 1840. Reprinted in Essays from the Edinburgh and Quarterly Reviews (London: Longman et al.), pp. 63}141
  9. ^ Secchi, A. (1879) Lezioni elementari di fisica terrestre: coll'aggiunta di due discorsi sopra la grandezza del creato; opera compilata da scritti inediti (Torino and Rome: Ermanno Loescher)
  10. ^ Sergent, E. (1868) Compendio di fisica terrestre e geograxa: ad uso dei giovanetti delle scuole elementari, tecniche e ginnasiali e degli allievi delle scuole popolari e professionali (Milan: Presso Carlo Barbini).
  11. ^ Denza, F. (1882) La meteorologia e la fisica terrestre: al III congresso geograxco internazionaledi Venezia (Rome).
  12. ^ Özçep, F., Orbay, N., (2002). Jeofizik ve Tarihsel Gelişimi, İstanbul Universitesi yayınları, Yayın No:4347, 446 Sayfa, İstanbul
  13. ^ Schröder, Wilfried (1982). Disziplingeschichte als wissenschaftliche Selbstreflexion historische Wissenschaftsforschung. Europäische Hochschulschriften: Physik 7. Lang. ISBN 978-3-8204-5960-9. 
  14. ^ Schröder, Wilfried (1982). "Emil Wiechert und seine Bedeutung für die Entwicklung der Geophysik zur exakten Wissenschaft". Archive for history of exact sciences 27 (4). doi:10.1007/BF00328005. 

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