Peter Lesley (September 17, 1819 - 1903) was an American geologist and mining engineer, and one of the founding members of the United States Geological Survey (USGS). He began his career with the Pennsylvania Geological Survey, where he conducted extensive geological mapping of the state. In the 1860s, Lesley played a key role in establishing the USGS and held significant positions within the organization. He made substantial contributions to coal and iron ore geology, and was recognized as a member of the American Association for the Advancement of Science. Lesley's work in geological surveying and mineral exploration greatly influenced the development of American mining geology in the 19th century.
