The story
The society was founded in Ithaca, New York, in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchcock, John R. Procter and Edward Orton and has been headquartered at 3300 Penrose Place, Boulder, Colorado, US, since 1967.
GSA began with 100 members under its first president, James Hall. In 1889 Mary Emilie Holmes became its first female member. It grew slowly but steadily to 600 members until 1931, when a nearly $4 million endowment from 1930 president R. A. F. Penrose Jr. jumpstarted GSA's growth. As of December 2017, GSA had more than 25,000 members in over 100 countries.
The society has six regional sections in North America and twenty-two scientific divisions. The oldest such regional interest group is the Cordilleran section, which first met December 29–30, 1899 at the California Academy of Sciences in San Francisco. At the time, travel back east was difficult for western geologists during that period of the year. This led to the foundation of a regional geological club.
From Wikipedia’s article on Geological Society of America, shared under CC BY-SA 4.0.4