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Marine Isotope Stage 9
Marine Isotope Stage 9 (MIS 9) is a Marine Isotope Stage in the geological record. It is the final period of the Lower Paleolithic, and lasts from 337,000 to 300,000 years ago according to Lisiecki and Raymo's LR04 Benthic Stack, which has been adopted by the Subcommission on Quaternary Stratigraphy of the International Commission on Stratigraphy. It was an interglacial (warm period) which corresponds to the Purfleet Interglacial in Britain, and falls within the Pre-Illinoian in North America. Some authorities regard it as corresponding to the Holstein Interglacial in continental Europe. Europe was then occupied by ''Homo heidelbergensis'', but they had probably retreated from Britain during the preceding glacial period. Populations returned as the climate warmed and sea levels rose around 330,000 years ago, and thousands of hand axes and other artefacts have been found along the terraces of the Thames and former Solent rivers. In Southern England, the summers were similar to or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Isotope Stage
Marine isotope stages (MIS), marine oxygen-isotope stages, or oxygen isotope stages (OIS), are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data reflecting changes in temperature derived from data from deep sea core samples. Working backwards from the present, which is MIS 1 in the scale, stages with even numbers have high levels of oxygen-18 and represent cold glacial periods, while the odd-numbered stages are lows in the oxygen-18 figures, representing warm interglacial intervals. The data are derived from pollen and foraminifera (plankton) remains in drilled marine sediment cores, sapropels, and other data that reflect historic climate; these are called proxies. The MIS timescale was developed from the pioneering work of Cesare Emiliani in the 1950s, and is now widely used in archaeology and other fields to express dating in the Quaternary period (the last 2.6 million years), as well as providing the fullest and best data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lower Paleolithic
The Lower Paleolithic (or Lower Palaeolithic) is the earliest subdivision of the Paleolithic or Old Stone Age. It spans the time from around 3 million years ago when the first evidence for stone tool production and use by hominins appears in the current archaeological record, until around 300,000 years ago, spanning the Oldowan ("mode 1") and Acheulean ("mode 2") lithics industries. In African archaeology, the time period roughly corresponds to the Early Stone Age, the earliest finds dating back to 3.3 million years ago, with Lomekwian stone tool technology, spanning Mode 1 stone tool technology, which begins roughly 2.6 million years ago and ends between 400,000 and 250,000 years ago, with Mode 2 technology. The Middle Paleolithic followed the Lower Paleolithic and recorded the appearance of the more advanced prepared-core tool-making technologies such as the Mousterian. Whether the earliest control of fire by hominins dates to the Lower or to the Middle Paleolithic remai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lorraine Lisiecki
Lorraine Lisiecki is an American paleoclimatologist. She is a professor in the Department of Earth Sciences at the University of California, Santa Barbara. She has proposed a new analysis of the 100,000-year problem in the Milankovitch theory of climate change. She also created the analytical software behind the LR04, a "standard representation of the climate history of the last five million years". Education Lisiecki graduated in 1995 from the South Carolina Governor’s School for Science and Mathematics. Lisiecki received her B.Sc. in Earth, Atmospheric, and Planetary Science in 1999 and also obtained an M.Sc. in Geosystems in 2000 from the Massachusetts Institute of Technology. She earned a M.Sc. and Ph.D. in Geological Sciences, both from Brown University in 2003 and 2005. Lisiecki's Ph.D. thesis was titled “''Paleoclimate time series: New alignment and compositing techniques, a 5.3-Myr benthic δ18O stack, and analysis of Pliocene-Pleistocene climate transitions''”. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Commission On Stratigraphy
The International Commission on Stratigraphy (ICS), sometimes referred to unofficially as the "International Stratigraphic Commission", is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphy, stratigraphical, geology, geological, and chronology, geochronological matters on a global scale. It is the largest subordinate body of the International Union of Geological Sciences (IUGS). The ICS is essentially a permanent working committee, working subcommittee, which meets far more regularly than the quadrennial meetings scheduled by the IUGS, when it meets as a congress or committee, membership of the whole. Aims One of its main aims, a project begun in 1974, is to establish a multidisciplinary standard and global geologic time scale that will ease paleontology, paleontological and geobiology, geobiological comparisons region to region by benchmarks with stringent and rigorous strata criteria called Global Boundary Stratotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interglacial
An interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago. Pleistocene During the 2.5 million years of the Pleistocene, numerous glacials, or significant advances of continental ice sheets, in North America and Europe, occurred at intervals of approximately 40,000 to 100,000 years. The long glacial periods were separated by more temperate and shorter interglacials. During interglacials, such as the present one, the climate warms and the tundra recedes polewards following the ice sheets. Forests return to areas that once supported tundra vegetation. Interglacials are identified on land or in shallow epicontinental seas by their paleontology. Floral and faunal remains of species pointing to temperate climate and indicating a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pre-Illinoian
The Pre-Illinoian Stage is used by Quaternary geologists for the early and middle Pleistocene glacial and interglacial periods of geologic time in North America from ~2.5–0.2 Ma (million years ago). North America As the oldest stage in the North American regional subdivision of the Quaternary, the Pre-Illinoian precedes the Illinoian Stage. Researchers have identified 11 distinct glacial stages during the Pre-Illinoian Stage. The Pleistocene prior to the Illinoian stage had previously been subdivided into the Nebraskan, Aftonian, Kansan, and Yarmouthian stages (ages). However, detailed studies of these stages revealed that the assumptions and criteria on which they were defined proved to be wrong to such a point that these stages became meaningless in terms of the actual glacial–interglacial record. For example, instead of two glaciations having occurred prior to the Illinoian Stage, researchers found that 11 distinct glaciations had occurred. In addition, what was p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Heidelbergensis
''Homo heidelbergensis'' (also ''H. sapiens heidelbergensis''), sometimes called Heidelbergs, is an extinct species or subspecies of archaic human which existed during the Middle Pleistocene. It was subsumed as a subspecies of ''H. erectus'' in 1950 as ''H. e. heidelbergensis'', but towards the end of the century, it was more widely classified as its own species. It is debated whether or not to constrain ''H. heidelbergensis'' to only Europe or to also include African and Asian specimens, and this is further confounded by the type specimen (Mauer 1) being a jawbone, because jawbones feature few diagnostic traits and are generally missing among Middle Pleistocene specimens. Thus, it is debated if some of these specimens could be split off into their own species or a subspecies of ''H. erectus''. Because the classification is so disputed, the Middle Pleistocene is often called the "muddle in the middle." ''H. heidelbergensis'' is regarded as a chronospecies, evolving from an Africa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hand Axe
A hand axe (or handaxe or Acheulean hand axe) is a prehistoric stone tool with two faces that is the longest-used tool in human history, yet there is no academic consensus on what they were used for. It is made from stone, usually flint or chert that has been "reduced" and shaped from a larger piece by knapping, or hitting against another stone. They are characteristic of the lower Acheulean and middle Palaeolithic (Mousterian) periods, roughly 1.6 million years ago to about 100,000 years ago, and used by ''Homo erectus'' and other early humans, but rarely by ''Homo sapiens''. Their technical name (biface) comes from the fact that the archetypical model is a generally bifacial (with two wide sides or faces) and almond-shaped (amygdaloidal) lithic flake. Hand axes tend to be symmetrical along their longitudinal axis and formed by pressure or percussion. The most common hand axes have a pointed end and rounded base, which gives them their characteristic almond shape, and both f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thames
The River Thames ( ), known alternatively in parts as the River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the second-longest in the United Kingdom, after the River Severn. The river rises at Thames Head in Gloucestershire, and flows into the North Sea near Tilbury, Essex and Gravesend, Kent, via the Thames Estuary. From the west it flows through Oxford (where it is sometimes called the Isis), Reading, Henley-on-Thames and Windsor. The Thames also drains the whole of Greater London. In August 2022, the source of the river moved five miles to beyond Somerford Keynes due to the heatwave in July 2022. The lower reaches of the river are called the Tideway, derived from its long tidal reach up to Teddington Lock. Its tidal section includes most of its London stretch and has a rise and fall of . From Oxford to the Estuary the Thames drops by 55 metres. Running through some of the drier parts of mai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Solent
The River Solent is a now-extinct river which during the Paleocene would have flowed around the area which is now the coastlines of Hampshire and the Isle of Wight. History The River Solent was one of three major rivers in central and southern England, together with the Proto-Thames and Bytham, but unlike the other two it was not destroyed by the extreme Anglian Glaciation around 450,000 years ago. It became extinct after flooding following the end of the last ice age, becoming submerged and incorporated into the Solent, a strait of the English Channel that sits between the Isle of Wight and Hampshire. The River Solent's source was the River Frome, and the River Solent's tributaries, the River Test, River Itchen, the River Avon and the River Medina, still survive today. Several towns on both the South Coast and the Isle of Wight are built near features of the River Solent - Cowes and East Cowes are built around the mouth of the River Medina, which formed due to the floodin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clactonian
The Clactonian is the name given by archaeologists to an industry of European flint tool manufacture that dates to the early part of the interglacial period known as the Hoxnian, the Mindel-Riss or the Holstein stages (c. 400,000 years ago). Clactonian tools were made by ''Homo heidelbergensis''. It is named after 400,000-year-old finds made by Hazzledine Warren in a palaeochannel at Clacton-on-Sea in the English county of Essex in 1911. The artifacts found there included flint chopping tools, flint flakes and the tip of a worked wooden shaft along with the remains of a giant elephant and hippopotamus. Further examples of the tools have been found at sites including Barnfield Pit and Rickson's Pit, near Swanscombe in Kent and Barnham in Suffolk; similar industries have been identified across Northern Europe. The Clactonian industry involved striking thick, irregular flakes from a core of flint, which was then employed as a chopper. The flakes would have been used as crude kniv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
