In 1785 he presented a paper entitled Theory of the Earth to the Royal Society of Edinburgh.
William Smith (1769–1839) drew some of the first geological maps and began the process of ordering rock strata (layers) by examining the fossils contained in them.
James Hutton is often viewed as the first modern geologist.
It is bracketed at the old end by the dates of the earliest solar system material at 4.567 Ga, (gigaannum: billion years ago) and the age of the Earth at 4.54 Ga at the beginning of the informally recognized Hadean eon.
At the young end of the scale, it is bracketed by the present day in the Holocene epoch.
The word geology was first used by Ulisse Aldrovandi in 1603, then by Jean-André Deluc in 1778 and introduced as a fixed term by Horace-Bénédict de Saussure in 1779.
The word is derived from the Greek γῆ, gê, meaning "earth" and λόγος, logos, meaning "speech".
Geology (from the Greek γῆ, gê, "earth" and λόγος, logos, "study") is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change.
Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).
Abu al-Rayhan al-Biruni (973–1048 CE) was one of the earliest Muslim geologists, whose works included the earliest writings on the geology of India, hypothesizing that the Indian subcontinent was once a sea.
Islamic Scholar Ibn Sina (Avicenna, 981–1037) proposed detailed explanations for the formation of mountains, the origin of earthquakes, and other topics central to modern Geology, which provided an essential foundation for the later development of the science.
Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates.