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  2. Late Miocene - Wikipedia

    en.wikipedia.org/wiki/Late_Miocene

    The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene Epoch made up of two stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma ( million years ago ) to 5.333 Ma.

  3. Aquitanian (stage) - Wikipedia

    en.wikipedia.org/wiki/Aquitanian_(stage)

    The Aquitanian Stage was named after the Aquitaine region in France and was introduced in scientific literature by Swiss stratigrapher Karl Mayer-Eymar in 1858.. The base of the Aquitanian (also the base of the Miocene Series and the Neogene System) is defined as the place in the stratigraphic column at the first appearance of foram species Paragloborotalia kugleri, the extinction of ...

  4. Piacenzian - Wikipedia

    en.wikipedia.org/wiki/Piacenzian

    The late Piacenzian may be when the genus Homo developed out of the ancestral genus Australopithecus. [13] While the oldest known fossils unambiguously identified as Homo habilis date to just after the end of the Piacenzian (2.58 Ma), a fossilized jawbone that exhibits traits that are transitional between Australopithecus and Homo habilis was ...

  5. Quaternary - Wikipedia

    en.wikipedia.org/wiki/Quaternary

    The Quaternary (/ k w ə ˈ t ɜːr n ə r i, ˈ k w ɒ t ər n ɛr i / kwə-TUR-nə-ree, KWOT-ər-nerr-ee) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the Phanerozoic eon. [3]

  6. Quaternary science - Wikipedia

    en.wikipedia.org/wiki/Quaternary_science

    The Quaternary Period is a geologic time period that can be separated into two epochs, the Pleistocene ("most recent") Epoch, generally defined as beginning about 2.58 million years ago, and the Holocene ("wholly modern") Epoch, which began about 11,700 years ago. [5] [6] The study of Quaternary science began in the late eighteenth century in ...

  7. Quaternary (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Quaternary_(chemistry)

    Quaternary is a term used in organic chemistry to classify various types of compounds (e. g. amines and ammonium salts). [1]

  8. Quaternary compound - Wikipedia

    en.wikipedia.org/wiki/Quaternary_compound

    In chemistry, a quaternary compound is a compound consisting of exactly four chemical elements. In another use of the term in organic chemistry , a quaternary compound is or has a cation consisting of a central positively charged atom with four substituents, especially organic ( alkyl and aryl ) groups, discounting hydrogen atoms.

  9. Hemisyntrachelus - Wikipedia

    en.wikipedia.org/wiki/Hemisyntrachelus

    This genus is known in the fossil records from the latest Miocene to the Quaternary (age range: from 5.332 to 1.806 million years ago). Fossils are found in the marine strata of Italy, the Netherlands, the Bahía Inglesa Formation of the Caldera Basin, Chile and in the fossiliferous Pisco Formation of Peru.