Geologic time scale - Wikipedia
The following table summarises the major events and characteristics of the divisions making up the geologic time scale of Earth. This table is arranged with the most recent geologic periods at the top, and the oldest at the bottom.
Geologic Time Scale - Geology (U.S. National Park Service)
2021年10月5日 · Geologic time scale showing the geologic eons, eras, periods, epochs, and associated dates in millions of years ago (MYA). The time scale also shows the onset of major evolutionary and tectonic events affecting the North American continent and the Northern Cordillera (SCAK, south-central Alaska; SEAK, southeast Alaska; NAK, northern Alaska; CAK ...
Currently, the Anthropocene has an informal designation, with a proposed age span extending from the present to a beginning point between ca. 15,000 yr B.P. and as recent as 1960 CE. The Cenozoic, Mesozoic, and Paleozoic are the Eras of the Phanerozoic Eon.
GSA Geologic Time Scale - Geological Society of America
At GSA you'll find the resources, confidence, and connections you need to reach fulfilling new heights in your geoscience career.
Geologic Time Scale - Major Divisions of Geologic Time Chart
Effective communication in the geosciences requires consistent uses of stratigraphic nomenclature, especially divisions of geologic time. A geologic time scale is composed of standard stratigraphic divisions based on rock sequences and …
Geologic time | Periods, Time Scale, & Facts | Britannica
2025年1月17日 · Geologic time, the extensive interval of time occupied by the geologic history of Earth. Formal geologic time begins with the Archean Eon (4.0 billion to 2.5 billion years ago) and continues to the present day. Modern geologic time scales also include the Hadean Eon (4.6 billion to 4.0 billion years ago).
Geologic Time Scale Recently updated - Science Notes and Projects
2025年1月11日 · Tables of the Geologic Time Scale. The four eons are the Hadean, Archean, Proterozoic, and Phanerozoic. The Hadean era lasted around 600 million years and includes the formation of the Earth and Moon. The Archean era lasted around 1.5 billion years, encompassing the formation of the crust and the first stirrings of life.
Geologic Time Scale | U.S. Geological Survey - USGS.gov
The Geologic Time Scale above is a helpful reference to use along with the information provided below. The left half shows a timeline of Earth’s geologic history which is split into Eons, Eras, Periods, and Epochs and how many millions of years ago (MYA) these occurred.
The scale of geologic time is vast, currently estimated at nearly 4.6 billion years. During that time, life evolved into the familiar forms we see today. These materials are provided to assist in understanding time relationships and how life on Earth changed through time. The dates shown were compiled from several available sources. Table 1 ...
Names of units and age boundaries follow the Gradstein et al. (2012) and Cohen et al. (2012) compilations. Age estimates and picks of boundaries are rounded to the nearest whole number (1 Ma) for the pre-Cenomanian, and rounded to one decimal place (100 ka) for the Cenomanian to Pleistocene interval.