The geologic time scale is a way of representing deep time based on events that have occurred through Earth's history, a time span of about 4.54 ± 0.05 billion years. [3]

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Dec 1, 2025 · The geologic time scale is the “calendar” for events in Earth history. It subdivides all time into named units of abstract time called—in descending order of duration— eons, eras, …

Jan 11, 2025 · The Geologic Time Scale or Geological Time Scale (GTS) is a chronological framework that organizes Earth’s history into various units based on geological and …

Feb 13, 2023 · The geologic time scale (GTS) is a chronological framework that organizes Earth’s 4.6 billion-year history based on major geological and biological events. It allows scientists to …

Oct 5, 2021 · Geologic time scale showing the geologic eons, eras, periods, epochs, and associated dates in millions of years ago (MYA).

May 13, 2025 · Scientists use the geologic time scale to organize Earth's long history into eons, eras, and periods. The Phanerozoic eon is known for the appearance and dominance of …

Explore the geologic timescale and understand Earth's history through the University of California Museum of Paleontology's comprehensive guide.

Geologists do this to be precise about the time in which a geologic event occurs. Figure 7.1.1 The Geologic Time Scale – Earth’s History over the past 4.55 billion years divided into Eons, Eras, …

Scientists have put together the geologic time scale to describe the order and duration of major events on Earth for the last 4 1 ⁄ 2 billion years.