Modern geology has been formed by an interplay of
catastrophism and uniformitarianism. James Hall the Neptunist was
a good friend of James Hutton the Plutonist who first suggested
uniformitarianism; Hutton helped convert Hall to Plutonism.
Charles Lyell was a good friend of Charles Darwin; Darwin helped
convert Lyell to believe in evolution.
See also in The book of science:
Readings on wikipedia: