Esther Applin, American geologist and paleontologist (d. 1972)
Esther Applin (November 24, 1895 – July 23, 1972) was an American geologist and paleontologist. Applin completed her Bachelor of Arts degree in 1919 from the University of California, Berkeley. Later, she completed a Master's degree which was focused on microfossils. She was a leading figure in the use of microfossils to determine the age of rock formation for use in oil exploration in the Gulf of Mexico region. Her job was to examine microfossils, especially the Foraminifera, that were collected in drill holes to determine the age of the rock into which the company was drilling. Applin's discoveries were crucial to successful drilling operations across the entire oil industry. Additionally, her contribution to geology, more specifically in the study of micropaleontology, put women geologists on the map, and was pivotal in making them as respected as men in the geological field of science.