Editing Geophysics (section)

{{short description|Physics of the Earth and its vicinity}}
{{Use dmy dates|date=April 2014}}
{{Geophysics}}

'''Geophysics''' ({{IPAc-en|ˌ|dʒ|iː|oʊ|ˈ|f|ɪ|z|ɪ|k|s}}) is a subject of [[natural science]] concerned with the physical processes and [[Physical property|properties]] of [[Earth]] and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct investigations across a wide range of scientific disciplines. The term ''geophysics'' classically refers to [[solid earth]] applications: Earth's [[figure of the Earth|shape]]; its [[gravitational]], [[Earth's magnetic field|magnetic fields]], and [[electromagnetic field]]s; its [[structure of the Earth|internal structure]] and [[Earth#Chemical composition|composition]]; its [[geodynamics|dynamics]] and their surface expression in [[plate tectonics]], the generation of [[magma]]s, [[volcanism]] and rock formation.<ref name=Sheriff1991>{{harvnb|Sheriff|1991}}</ref> However, modern geophysics organizations and pure scientists use a broader definition that includes the [[water cycle]] including snow and ice; [[geophysical fluid dynamics|fluid dynamics]] of the oceans and the [[atmosphere]]; [[atmospheric electricity|electricity]] and [[magnetism]] in the [[ionosphere]] and [[magnetosphere]] and [[solar-terrestrial physics]]; and analogous problems associated with the [[Moon]] and other planets.<ref name=Sheriff1991/><ref name=IUGG>{{harvnb|IUGG|2011}}</ref><ref name=AGUscience>{{harvnb|AGU|2011}}</ref><ref name="Gutenberg (1929)">Gutenberg, B., 1929, Lehrbuch der Geophysik. Leipzig. Berlin (Gebruder Borntraeger).</ref><ref name="Runcorn">Runcorn, S.K, (editor-in-chief), 1967, International dictionary of geophysics:. Pergamon, Oxford, 2 volumes, 1,728 pp., 730 fig</ref><ref name="Geophysics">Geophysics, 1970, Encyclopaedia Britannica, Vol.10, p. 202-202</ref>

Although geophysics was only recognized as a separate discipline in the 19th century, its origins date back to ancient times. The first magnetic compasses were made from [[lodestone]]s, while more modern magnetic compasses played an important role in the history of navigation. The first seismic instrument was built in 132 AD. [[Isaac Newton]] applied his theory of mechanics to the tides and the [[precession of the equinox]]; and instruments were developed to measure the Earth's shape, density and gravity field, as well as the components of the water cycle. In the 20th century, geophysical methods were developed for remote exploration of the solid Earth and the ocean, and geophysics played an essential role in the development of the theory of plate tectonics.

Geophysics is pursued for fundamental understanding of the Earth its space environment. Geophysics often addresses societal needs, such as [[mineral resources]], assessment and [[Mitigation#Disaster_mitigation|mitigation]] of [[natural hazards]] and [[environmental impact assessment]].<ref name=IUGG/>  In [[exploration geophysics]], [[geophysical survey]] data are used to analyze potential petroleum reservoirs and mineral deposits, locate groundwater, find archaeological relics, determine the thickness of glaciers and soils, and assess sites for [[environmental remediation]].
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