Uniformitarianism is the assumption that the geological layers of the earth were not formed by Divine intervention, but by natural phenomena identical to those of today: erosion, flooding, earthquakes, etc.

Uniformitarian geology was based on careful observation of sequences of natural strata, many exposed during canal and railroad construction during the Industrial Revolution. Although hotly contested by Catastrophists such as Oxfordian professor William Buckland (above), the Uniformitarian view won out.