Assessment Questions 1.7

Lyell's fundamental assertion was that all past changes on Earth were brought about by the slow agency of existing causes. This means that the geological features we observe today were shaped over extended periods through gradual processes.

Lyell played a crucial role in challenging traditional views and promoting the concept of uniformitarianism, which suggests that geological features are a result of slow, continuous processes over vast periods.

Lyell applied the principle of uniformitarianism to estimate the ages of geological features. For instance, he calibrated the modern growth rate of the Mississippi Delta to suggest it would take 100,000 years to attain its size.