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American Geophysical Union was created in 1919.
Canadian Geophysical Union was created in 1974.
The American Geophysical Union, the Environmental and Engineering Geophysical Society, the Seismological Society of America, and the Society of Exploration Geophysicists maintain membership lists that include geophysicists.
Western Geophysical was created in 1933.
Geophysical Service was created in 1930.