Scottish Geologist: Considered one of the most influential geologists of the 19th century, Sir Charles Lyell made significant contributions to our understanding of the Earth's history https://www.britannica.com/summary/Charles-Lyell.Uniformitarianism: Lyell's most famous theory is uniformitarianism, which proposes that the geological processes we see shaping the Earth today (like erosion and sedimentation) have been happening for vast stretches of time https://evolution.berkeley.edu/the-history-of-evolutionary-thought/1800s/uniformitarianism-charles-lyell/. This contrasted with prevailing ideas of catastrophic events shaping the Earth's features.Principles of Geology: His influential book, "Principles of Geology," published in multiple volumes, outlined his ideas on uniformitarianism and provided evidence for the immense age of the Earth https://en.wikipedia.org/wiki/Principles_of_Geology.Influence on Darwin: Charles Lyell's work on deep time greatly influenced Charles Darwin's theory of evolution by natural selection. The vast stretches of time implied by uniformitarianism allowed for gradual evolutionary change over millions of years https://evolution.berkeley.edu/the-history-of-evolutionary-thought/1800s/uniformitarianism-charles-lyell/.
