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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.
This is a list of such named time periods as defined in various fields of study. ... Geologic Time – Period prior to humans. 4.6 billion to 3 million years ago ...
The Precambrian includes approximately 90% of geologic time. It extends from 4.6 billion years ago to the beginning of the Cambrian Period (about 539 Ma).It includes the first three of the four eons of Earth's prehistory (the Hadean, Archean, and Proterozoic) and precedes the Phanerozoic eon.
Earth formed in this manner about 4.54 billion years ago (with an uncertainty of 1%) [25] [26] [4] and was largely completed within 10–20 million years. [27] In June 2023, scientists reported evidence that the planet Earth may have formed in just three million years, much faster than the 10−100 million years thought earlier.
Basin Groups Era begins on Earth. c. 4,450 Ma – 100 million years after the Moon formed, the first lunar crust, formed of lunar anorthosite, differentiates from lower magmas. The earliest Earth crust probably forms similarly out of similar material. On Earth the pluvial period starts, in which the Earth's crust cools enough to let oceans form.
See calendar and list of calendars for other groupings of years. See history, history by period, and periodization for different organizations of historical events. For earlier time periods, see Timeline of the Big Bang, Geologic time scale, Timeline of evolution, and Logarithmic timeline.
Paleolithic c. 1.36 million years ago Neolithic period c. 10,000 – 2100 BCE Ancient China c. 2100 – 221 BCE Imperial period c. 221 BCE – 1911 CE Modern period. Americas North America North America: Lithic/Paleo-Indian (pre 8000 BCE) Archaic (c. 8000 – 1000 BCE) Woodland (1000 BCE to 1000 CE) Mississippian (800 CE to 1600 CE) Mesoamerica ...
era Archean ICS Plumb, 1991 Mesoproterozoic: 1,600 1,000 era ICS Hofmann, 1987 Mesozoic: 251.0 ± 0.7 65.5 ± 0.3 era ICS middle life: Philips, 1818 Messinian: 7.246 5.332 age Miocene ICS Messina (Italy) Mayer-Eymar, 1867 Miaogoalingian: 422 418.7 age Silurian China Miaolingian: 509 497 Epoch Cambrian ICS Migneintian: 486 478.6 ± 1.7 age ...