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MIS 9
Marine Isotope Stage 9 (MIS 9) was an interglacial (warm) Marine Isotope Stage. It was the last period of the Lower Paleolithic. Estimates of its dating vary. It lasted from 337,000 to 300,000 years ago according to Lisiecki and Raymo's 2005 LR04 Benthic Stack, whereas Rawlinson et al dated it in 2022 to between 328,000 and 301,000 years ago. It corresponds to the Purfleet Interglacial in Britain, and the Holstein Interglacial in continental Europe. Views on its division into sub-stages also vary. A 2013 study divided it into two warm interstadials (9a and 9c) and one cooler stadial (9b), whereas a 2025 study had three warm sub-stages (9a, 9c and 9e) and two which were cooler (9b and 9d). MIS Drivers Marine Isotope Stages are glacial and interglacial periods throughout time. One of the processes that drive this major change are the Milankovitch Cycles, which control the insolation received from the Sun. The data is retrieved from deep sea core samples. The manner by which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe Middle Pleistocene Glacial Cycles
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...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 Hoxnian Interglacial (corresponding to the global Marine Isotope Stage 11 and the continental Holstein Interglacial) around 424–415,000 years ago. Clactonian tools were made by ''Homo heidelbergensis''. The Clactonian is primarily distinguished from the (globally) contemporaneous Acheulean industry by its lack of use of handaxe tools. It is named after finds made by Samuel Hazzledine Warren in a palaeochannel at Clacton-on-Sea in the English county of Essex in 1911. The artefacts found there included flint chopping tools, flint flakes and the tip of a worked wooden shaft, the Clacton Spear. 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 stri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hand Axe
A hand axe (or handaxe or Acheulean hand axe) is a Prehistory, prehistoric stone tool with two faces that is the longest-used tool in human history. 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 Symmetry, symmetrical along their longitudinal Symmetry axis, 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 faces have been Knapping, knap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Heidelbergensis
''Homo heidelbergensis'' is a species of archaic human from the Middle Pleistocene of Europe and Africa, as well as potentially Asia depending on the taxonomic convention used. The species-level classification of ''Homo'' during the Middle Pleistocene is controversial, called the "muddle in the middle", owing to the wide anatomical range of variation that populations exhibited during this time. ''H. heidelbergensis'' has been regarded as either the last common ancestor of modern humans, Neanderthals, and Denisovans; or as a completely separate lineage. ''H. heidelbergensis'' was species description, described by German anthropologist Otto Schoetensack in 1908 based on a jawbone, Mauer 1, from a sand mining, sand pit near the village of Mauer (Baden), Mauer — southeast of Heidelberg. It was the oldest identified human fossil in Europe, and Schoetensack described it as an antediluvian race (before the Great Flood) which would eventually evolve into living Europeans. By the mid-2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope Analysis
Isotope analysis is the identification of isotopic signature, abundance of certain stable isotopes of chemical elements within organic and inorganic compounds. Isotopic analysis can be used to understand the flow of energy through a food web, to reconstruct past environmental and climatic conditions, to investigate human and animal diets, for food authentification, and a variety of other physical, geological, palaeontological and chemical processes. Stable isotope ratios are measured using mass spectrometry, which separates the different isotopes of an element on the basis of their mass-to-charge ratio. Tissues affected Isotopic oxygen is incorporated into the body primarily through ingestion at which point it is used in the formation of, for archaeological purposes, bones and teeth. The oxygen is incorporated into the hydroxylcarbonic apatite of bone and tooth enamel. Bone is continually remodelled throughout the lifetime of an individual. Although the rate of tur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen-16
Oxygen-16 (symbol: 16O or ) is a nuclide. It is a stable isotope of oxygen, with 8 neutrons and 8 protons in its nucleus, and when not ionized, 8 electrons orbiting the nucleus. Oxygen-16 has a mass of . It is the most abundant isotope of oxygen and accounts for 99.757% of oxygen's natural abundance. The relative and absolute abundances of oxygen-16 are high because it is a principal product of stellar evolution and because it is a primordial isotope, meaning it can be made by stars that were initially made exclusively of hydrogen. Most oxygen-16 is synthesized at the end of the helium fusion process in stars; the triple-alpha process creates carbon-12, which captures an additional helium-4 to make oxygen-16. It is also created by the neon-burning process. Oxygen-16 is doubly magic. Solid samples (organic and inorganic) for oxygen-16 studies are usually stored in silver cups and measured with pyrolysis and mass spectrometry. Researchers need to avoid improper or prolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen-18
Oxygen-18 (, Ω) is a natural, stable isotope of oxygen and one of the environmental isotopes. is an important precursor for the production of fluorodeoxyglucose (FDG) used in positron emission tomography (PET). Generally, in the radiopharmaceutical industry, enriched water () is bombarded with hydrogen ions in either a cyclotron or linear accelerator, producing fluorine-18. This is then synthesized into FDG and injected into a patient. It can also be used to make an extremely heavy version of water when combined with tritium (hydrogen-3): or . This compound has a density almost 30% greater than that of natural water. The accurate measurements of rely on proper procedures of analysis, sample preparation and storage. Paleoclimatology In ice cores, mainly Arctic and Antarctic, the ratio of to (known as δ) can be used to determine the temperature of precipitation through time. Assuming that atmospheric circulation and elevation has not changed significantly over the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Pollen
Paleobotany or palaeobotany, also known as paleophytology, is the branch of botany dealing with the recovery and identification of plant fossils from geological contexts, and their use for the biological reconstruction of past environments (paleogeography), and the evolutionary history of plants, with a bearing upon the evolution of life in general. It is a component of paleontology and paleobiology. The prefix ''palaeo-'' or ''paleo-'' means "ancient, old", and is derived from the Greek adjective , . Paleobotany includes the study of land plants, as well as the study of prehistoric marine photoautotrophs such as photosynthetic algae, seaweeds or kelp. A closely related field is palynology, which is the study of fossilized and extant spores and pollen. Paleobotany is important in the reconstruction of ancient ecological and climate systems, known as paleoecology and paleoclimatology respectively. It is fundamental to the study of green plant development and evolution. Paleobot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foraminifera
Foraminifera ( ; Latin for "hole bearers"; informally called "forams") are unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and other uses; and commonly an external shell (called a "Test (biology), test") of diverse forms and materials. Tests of chitin (found in some simple genera, and ''Textularia'' in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthos, benthic, with different sized species playing a role within the macrobenthos, meiobenthos, and Benthos, microbenthos), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been id ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proxy (climate)
In the study of past climates ("paleoclimatology"), climate proxies are preserved physical characteristics of the past that stand in for direct meteorological measurements and enable scientists to reconstruct the climatic conditions over a longer fraction of the Earth's history. Reliable global records of climate only began in the 1880s, and proxies provide the only means for scientists to determine climatic patterns before record-keeping began. A large number of climate proxies have been studied from a variety of geologic contexts. Examples of proxies include stable isotope measurements from ice cores, growth rates in tree rings, species composition of sub-fossil pollen in lake sediment or foraminifera in ocean sediments, temperature profiles of boreholes, and stable isotopes and mineralogy of corals and carbonate speleothems. In each case, the proxy indicator has been influenced by a particular seasonal climate parameter (e.g., summer temperature or monsoon intensity) at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoclimatology
Paleoclimatology ( British spelling, palaeoclimatology) is the scientific study of climates predating the invention of meteorological instruments, when no direct measurement data were available. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to understand natural variation and the evolution of the current climate. Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere. The scientific field of paleoclimatology came to maturity in the 20th century. Notable periods studied by paleoclimatologists include the frequent glaciations that Earth has undergone, rapid cooling events like the Younger Dryas, and the rapid warming du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
