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  2. Geologic record - Wikipedia

    en.wikipedia.org/wiki/Geologic_record

    Comparing the record about the discordance in the record to the full rock column shows the non-occurrence of the missing species and that portion of the local rock record, from the early part of the middle Eocene is missing there. This is one form of discordancy and the means geologists use to compensate for local variations in the rock record.

  3. 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.

  4. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    Geologic time shown in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events. 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 ...

  5. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    The geologic record is the strata (layers) of rock in the planet's crust and the science of geology is much concerned with the age and origin of all rocks to determine the history and formation of Earth and to understand the forces that have acted upon it.

  6. Historical geology - Wikipedia

    en.wikipedia.org/wiki/Historical_geology

    Geologic Time Spiral. 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. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    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 such as paleomagnetism and stable isotope ratios .

  8. Scottish and Irish rocks may be rare record of ‘snowball ...

    www.aol.com/scottish-irish-rocks-may-rare...

    The Port Askaig Formation, which is made up of layers of rock up to 1.1km thick, was likely laid down between 662 and 720 million years ago. Scottish and Irish rocks may be rare record of ...

  9. Geological event - Wikipedia

    en.wikipedia.org/wiki/Geological_event

    Event stratigraphy was first proposed as a system for the recognition, study and correlation of the effects of important physical or biological events on the broader stratigraphical record. [1] Seismite in Holocene sediments of the Dead Sea basin, Israel. This is a record of an earthquake (a geological event) that disturbed the strata.