geologic time


Definition of geologic time

: the long period of time occupied by the earth's geologic history
geologic time table

Examples of geologic time in a Sentence

Recent Examples on the Web Scientists say the periodic exposure to the elements of big chunks of volcanic rock as a result of tectonic movement has, over a geologic time scale, influenced the Earth’s climate, even helping bring on ice ages. Peter Fimrite,, "Could putting pebbles on beaches help solve climate change?," 16 Dec. 2019 Her Hugo Award-winning Broken Earth books feature a supercontinent called the Stillness that is anything but—the very land is a geologic time bomb, ravaged by earthquakes and volcanic eruptions. Wired, "For N. K. Jemisin, World-Building Is a Lesson in Oppression," 12 Nov. 2019 In geologic time, the volcano under Yellowstone National Park will erupt again. Edward Lotterman, Twin Cities, "Real World Economics: Lessons seen in ill-fated water-rail plan," 9 Nov. 2019 The ocean’s pH has shifted on geologic time scales. Alejandra Borunda, National Geographic, "Ocean acidification, explained," 7 Aug. 2019 Fossils span geologic time from hundreds to even billions of years and are discovered in many rock types and settings. Erin Dimaggio, Smithsonian, "How Do Scientists Date Fossils?," 13 June 2019 These new divisions of geologic time will likely bring some order and clarity to an era defined by monumental change, but not all scientists agree that the new ages are the best way to reclassify recent history. Avery Thompson, Popular Mechanics, "According to Geologists, We're Living In a New Age," 18 July 2018 At its core lay the realization battered into him on his first journey down the Colorado about humanity’s impermanence in the face of geologic time and how the Earth remained in a continual state of flux. Johnforristerross, Longreads, "Taming the Great American Desert," 2 July 2018 Over geologic time, Earth’s CO2 is regulated by the balance between volcanic outgassing, which adds CO2 to the atmosphere, and CO2 removal by chemical weathering of rocks. Scott Denning, Washington Post, "May the 4th be with Earth, a perfect planet that’s not too Hoth or Tatooine," 4 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'geologic time.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of geologic time

1861, in the meaning defined above

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The first known use of geologic time was in 1861

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Statistics for geologic time

Last Updated

28 Dec 2019

Cite this Entry

“Geologic time.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2020.

More from Merriam-Webster on geologic time

Rhyming Dictionary: Words that rhyme with geologic time Encyclopedia article about geologic time

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