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  2. Geologic time scale - Wikipedia

    en.wikipedia.org/wiki/Geologic_time_scale

    The geologic time scale, proportionally represented as a log-spiral with some major events in Earth's history. A megaannus (Ma) represents one million (10 6) years. The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses ...

  3. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    The geological history of the Earth follows the major geological events in Earth's past based on the geological time scale, a system of chronological measurement based on the study of the planet's rock layers (stratigraphy). Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left ...

  4. Relative dating - Wikipedia

    en.wikipedia.org/wiki/Relative_dating

    Relative dating is the science of determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age (i.e., estimated age). In geology, rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another.

  5. Precambrian - Wikipedia

    en.wikipedia.org/wiki/Precambrian

    Precambrian supercontinents. The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of the landmass. The earliest known supercontinent was Vaalbara. It formed from proto-continents and was a supercontinent 3.636 billion years ago.

  6. Historical geology - Wikipedia

    en.wikipedia.org/wiki/Historical_geology

    Historical geology or palaeogeology is a discipline that uses the principles and methods of geology to reconstruct the geological history of Earth. [1] Historical geology examines the vastness of geologic time, measured in billions of years, and investigates changes in the Earth, gradual and sudden, over this deep time.

  7. Geology - Wikipedia

    en.wikipedia.org/wiki/Geology

    The geological time scale encompasses the history of the Earth. [13] It is bracketed at the earliest by the dates of the first Solar System material at 4.567 Ga [ 14 ] (or 4.567 billion years ago) and the formation of the Earth at 4.54 Ga [ 15 ] [ 16 ] (4.54 billion years), which is the beginning of the Hadean eon – a division of geological time.

  8. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    Geologic time is the timescale used to calculate dates in the planet's geologic history from its origin (currently estimated to have been some 4,600 million years ago) to the present day. Radiometric dating measures the steady decay of radioactive elements in an object to determine its age. It is used to calculate dates for the older part of ...

  9. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    Geochronology. An artistic depiction of the major events in the history of Earth. Geochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools ...