Applin, Esther Richards | "Subsurface Stratigraphy of the Coastal Plain of Texas and Louisiana"

Offprint of the paper proving that microfossils could be used to date the layers of the Earth’s crust and identify potential oil-bearing zones, a key insight of modern geology. An attractive copy in very nice condition.

Author Esther Richards Applin (1895-1972) was an petroleum geologist at the Rio Bravo Oil Company. “In a paper presented at a Geological Society meeting in 1921 by her supervisor at Rio Bravo, Applin suggested that microfossils could be used to date strata. She was ridiculed by more experienced geologists for her audacity... To verify her claim, Applin worked with Alva Ellisor and Hedwig Kniker to find ways to separate the fossils from the matrix of the cuttings. In 1925, the three coauthored a paper that detailed the sequences and oil-bearing zones in the Gulf Coast using microfossils” (Biographical Dictionary of Women in Science p. 46).