|
Hsandagolian
The Hsandagolian age is a period of geologic time (33.9 – 23.03 Ma) within the Oligocene epoch of the Paleogene used more specifically with Asian Land Mammal Ages. It follows the Kekeamuan and precedes the Tabenbulakian age. The Ulangochuian's lower boundary is the approximate base of the Rupelian The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian ... age and upper boundary is the approximate upper base of the Aquitanian. References Oligocene {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asian Land Mammal Ages
The Asian land mammal ages, acronym ALMA, establish a geologic timescale for prehistoric Asian fauna beginning 58.7 Mya during the Paleogene and continuing through to the Miocene ( Aquitanian) (23.03 Ma). These periods are referred to as ages, stages, or intervals and were established using geographic place names where fossil materials where obtained. The basic unit of measure is the first/last boundary statement. This shows that the first appearance event of one taxon is known to predate the last appearance event of another. If two taxa are found in the same fossil quarry or at the same stratigraphic horizon, then their age-range zones overlap. Ages *Tabenbulakian: Lower boundary 28.4 Ma. Upper boundary 23.03 Ma. *Hsandagolian: Lower boundary 33.9 Ma. Upper boundary 23.03 Ma. *Kekeamuan: Lower boundary 33.9 Ma. Upper boundary 28.4 Ma. *Houldjinian: Lower boundary 37.2 Ma. Upper boundary after 33.9 Ma. *Ergilian: Lower boundary before 37.2 Ma. Upper boundary after 33.9 Ma. *Ulang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kekeamuan
The Kekeamuan age is a period of geologic time (33.9–28.4 Ma) within the Early Oligocene Epoch of the Paleogene Period. It is used more specifically with Asian Land Mammal Ages. It follows the Houldjinian and precedes the Hsandagolian age. The Kekeamuan's upper boundary is the approximate base of the Chattian The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest stage ... age. References Oligocene {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tabenbulakian
The Tabenbulakian age is a period of geologic time (28.4–23.03 Ma) within the Oligocene Epoch of the late Paleogene Period and Miocene Epoch of the early Neogene Period, used more specifically with Asian Land Mammal Ages. It follows the Hsandagolian The Hsandagolian age is a period of geologic time (33.9 – 23.03 Ma) within the Oligocene epoch of the Paleogene used more specifically with Asian Land Mammal Ages. It follows the Kekeamuan and precedes the Tabenbulakian age. The Ulangochuian ... age. The Tabenbulakian's lower boundary is the approximate base of the Chattian age and upper boundary is the approximate base of the Aquitanian age. See also * * References Oligocene geochronology Oligocene Asia Miocene Asia Chattian . . Oligocene life Miocene life {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Time
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 (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mya (unit)
Mya may refer to: Brands and product names * Mya (program), an intelligent personal assistant created by Motorola * Mya (TV channel), an Italian Television channel * Midwest Young Artists, a comprehensive youth music program Codes * Burmese language, ISO 639-3 code is * Moruya Airport's IATA code * The IOC, license plate, and UNDP country code for Myanmar ("MYA") People * Mya (given name) * Mya (singer) (Mya Marie Harrison, born 1979), an American R&B singer-songwriter and actress * Bo Mya (1927–2006), nom de guerre of a Myanmar rebel leader, chief rapist of the Karen National Union Other uses * ''Mýa'' (album), a 1998 album by Mýa * ''Mya'' (bivalve), a genus of soft-shell clams * MYA (unit) for "million years ago", a science-related unit of time used in astronomy, geology and biology See also * A (motor yacht) (M/Y A), a superyacht * Maia (other) * Maya (other) Maya may refer to: Civilizations * Maya peoples, of southern Mexico and norther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene
The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago (annum, Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphy, stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, evolution of mammals, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rupelian
The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian Stage. Name The stage is named after the small river Rupel in Belgium, a tributary to the Scheldt. The Belgian Rupel Group derives its name from the same source. The name Rupelian was introduced in scientific literature by Belgian geologist André Hubert Dumont in 1850. The separation between the group and the stage was made in the second half of the 20th century, when stratigraphers saw the need to distinguish between lithostratigraphic and chronostratigraphic names. Stratigraphic definition The base of the Rupelian Stage (which is also the base of the Oligocene Series) is at the extinction of the foraminiferan genus ''Hantkenina''. An official GSSP for the base of the Rupelian has been assigned in 1992 (Massignano, Italy). The transitio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquitanian (stage)
The Aquitanian is, in the ICS' geologic timescale, the oldest age or lowest stage in the Miocene. It spans the time between 23.03 ± 0.05 Ma and 20.43 ± 0.05 Ma (million years ago) during the Early Miocene. It is a dry, cooling period. The Aquitanian succeeds the Chattian (the youngest age of the Oligocene) and precedes the Burdigalian. The Aquitanian Age overlaps with the Harrisonian, Agenian, Pareora, Landon, Otaian, and Waitakian Ages from various regional timescales. Stratigraphic definition The Aquitanian Stage was named after the region Aquitaine 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 calcareous nanoplankton species ''Reticulofenestra bisecta'' (which forms the base of nanoplankton b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
