Charles Lyell is considered by many to be the father of modern geology. His masterwork, Principles of Geology, published between 1830 and 1833, added scientific rigor to geologic interpretations of rocks and fossils. Lyell also became the first to propose the division of the Cenozoic era (the current geologic period) into epochs based solely on fossil evidence. This led to our current understanding of geologic time and the history of Earth.
Lyell was the eldest of ten children born to Scottish parents. His father was an active naturalist who had a large library, including many books on geology, which may have sparked Charles' interest in this subject. Lyell attended Oxford, studying mathematics, law, and geology.
Upon graduation he began a legal career, but he left it quickly to pursue his interest in geology. Although unskilled at first, Lyell quickly became expert through study and increasing practical experience. This, coupled with his knowledge of zoology, helped him to make sense of the rocks he studied in his travels.
Lyell was familiar with contemporary theories of the history of Earth and with various explanations for the geologic phenomena he observed. As he became more confident of his knowledge of geology, he became sure that the then-current reliance on catastrophic explanations for the formation of most of Earth's features was incorrect. Like most scientists of his time, Lyell believed Earth to be ancient; unlike his contemporaries, Lyell agreed with Scottish geologist James Hutton (1726-1797) that everyday phenomena, continuing over vast stretches of time, were sufficient explanation for mountains, oceans, and other large structures on Earth.
In 1830 Lyell began his best-known work, Principles of Geology, destined to become a three-volume exposition that formed the foundation of modern geology as a true science. In the first volume Lyell reintroduced Hutton's Uniformitarianism, the idea that geological change is the result of long-acting and relatively uniform processes. Lyell envisioned a "great year" in which all creatures rose, fell, and rose again. In other words, Lyell's Earth lacked directionality: it did not progress but cycled eternally. To illustrate, he wrote, "Then might those genera of animals return, of which the memorials are preserved in the ancient rocks of our continents. The huge iguanodon might reappear in the woods, and the ichthyosaur in the sea, while the pterodactyl might flit again through the umbrageous groves of tree-ferns." In this view Lyell was wrong, a fact he later admitted.
Lyell's second volume dealt with his observations on igneous and metamorphic rocks, noting that high temperatures can cause changes in rocks. Among the phenomena explained by this are the changes seen in sedimentary rock into which hot igneous rocks have intruded. Lyell's third volume dealt with paleontology and stratigraphy (the ordering and interpretation of layers of rock), in which he became the first to try to arrange more recent rocks in a coherent order, dividing them into epochs according to the fossils contained in various strata. This method of ordering and dating rock layers relative to one another is still used today.
Lyell's work inspired Charles Darwin, who carried Principles of Geology with him his voyage to South America that prompted him to formulate his theory of evolution. At one point Darwin commented on Principles of Geology that "The greatest merit of the Principles was that it altered the whole tone of one's mind, and therefore that, when seeing a thing never seen by Lyell, one yet saw it through his eyes." Lyell was knighted for scientific accomplishment at the age of 51, was named a baron at age 67, and died a year later, preceded in death by his beloved wife.
P. ANDREW KARAM