7.2: Geology as a historical science
- Page ID
- 22643
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Geology is the study of the Earth and its history. While some geologists study modern geological phenomena such as earthquakes and volcanic eruptions, much of the science is devoted to discovering the past events that shaped and created the world we live upon today. In this respect, geology is considered a historical science because it deals with events that happened long ago–typically long before humans had evolved. Just as a historian or archeologist uses available records, artifacts, and other clues to paint a picture of past human lives, a geologist reconstructs the past using preserved evidence such as clues from layers of rock and the minerals and fossils found within those rocks. Geology shares good company with other historical sciences, including much of evolutionary biology, climatology, and archaeology. Astronomy is another example of a historical science: it has taken billions of years for light leaving far away galaxies (that is, galaxies that are billions of light years away) to reach the Earth, so when viewing such galaxies using powerful telescopes like the Hubble Space Telescope, we are looking backwards in time. If some of these galaxies went dark right now, observers on Earth would not know it until billions of years from now.