Search results
Results from the WOW.Com Content Network
500 million years of climate change [7] The Phanerozoic eon, encompassing the last 542 million years and almost the entire time since the origination of complex multi-cellular life, has more generally been a period of fluctuating temperature between ice ages, such as the current age, and "climate optima", similar to what occurred in the ...
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 ...
The Miocene (/ ˈ m aɪ. ə s iː n,-oʊ-/ MY-ə-seen, -oh-) [6] [7] is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words μείων (meíōn, "less") and καινός (kainós, "new") [8] [9] and means "less recent" because it has 18% fewer modern marine invertebrates ...
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 chronostratigraphy (the process of relating strata to time) and geochronology (a scientific branch of geology that aims to ...
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.
The Neogene (/ ˈ n iː. ə dʒ iː n / NEE-ə-jeen, [6] [7]) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.04 million years ago to the beginning of the present Quaternary Period 2.58 million years ago.
The Carboniferous (/ ˌ k ɑːr b ə ˈ n ɪ f ər ə s / KAR-bə-NIF-ər-əs) [6] is a geologic period and system of the Paleozoic era that spans 60 million years from the end of the Devonian Period 358.86 Ma (million years ago) to the beginning of the Permian Period, 298.9 Ma.
The Neogene spans from 23.03 million to 2.58 million years ago. It features two epochs: the Miocene, and the Pliocene. [23] The Miocene Epoch spans from 23.03 to 5.333 million years ago and is a period in which grasses spread further, dominating a large portion of the world, at the expense of forests.