Which art movement was Georgia O'Keeffe involved in?

Georgia O'Keeffe is an American artist known for her role in the development of the American modernism movement. She is also considered the mother of American modernism.

O'Keeffe was born in 1887 in Sun Prairie, Wis., and passed away in 1986 in Sante Fe, N.M. Her artwork consisted of mostly abstract work inspired by nature. She has a substantial body of work that she produced for over 70 years, which is on display in Asia, Europe and America. Some of her famous paintings include "Blue II" from 1916, "Petunia No. 2" from 1924, "Radiator Building - Night, New York" from 1927 and "Black Place, Grey and Pink" from 1949.