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Archaeometry
Archaeological science consists of the application of scientific techniques to the analysis of archaeological materials and sites. It is related to methodologies of archaeology. Martinón-Torres and Killick distinguish ‘scientific archaeology’ (as an epistemology) from ‘archaeological science’ (the application of specific techniques to archaeological materials). Martinón-Torres and Killick claim that ‘archaeological science’ has promoted the development of high-level theory in archaeology. However, Smith rejects both concepts of archaeological science because neither emphasize falsification or a search for causality. In the United Kingdom, the Natural and Environmental Research Council provides funding for archaeometry separate from the funding provided for archaeology. Types of archaeological science Archaeological science can be divided into the following areas: * physical and chemical dating methods which provide archaeologists with absolute and relative c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiocarbon Dating
Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for Chronological dating, determining the age of an object containing organic material by using the properties of carbon-14, radiocarbon, a radioactive Isotopes of carbon, isotope of carbon. The method was developed in the late 1940s at the University of Chicago by Willard Libby. It is based on the fact that radiocarbon () is constantly being created in the Atmosphere of Earth, Earth's atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter the amount of it contains begins to decrease as the undergoes radioactive decay. Measuring the amount of in a sample from a dead plant or animal, such as a piece of w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absolute Dating
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as use of the word "absolute" implies an unwarranted certainty of accuracy. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events. In archaeology, absolute dating is usually based on the physical, chemical, and life properties of the materials of artifacts, buildings, or other items that have been modified by humans and by historical associations with materials with known dates (such as coins and historical records). For example, coins found in excavations may have their production date written on them, or there may be written records describing the coin and when it was used, allowing the site to be associated with a particular calendar year. Absolute dating techniques include radiocarbon dating of wood o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeometallurgy
Archaeometallurgy is the study of the past use and production of metals by humans. It is a sub-discipline of archaeology and archaeological science. Uses Archaeometallurgical study has many uses in both the chemical and anthropological fields. Analysis contributes valuable insights into many archaeological questions, from technological choice to social organisation. Any project concerned with the relationship that the human species has had to the metals known to us is an example of archaeometallurgical study. Methods There are various methodological approaches to archaeometallurgical studies. The same methods used in analytical chemistry may be used to analyze artifacts. Chemical analysis methods may include the analysis of mass, density or chemical composition. Most methods are non-destructive in nature, such as X-ray spectroscopy, or micro-destructive (requiring removal of only a tiny portion of the sample). Non-destructive methods can be used on more artefacts than destructive on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dating Methodologies In Archaeology
Chronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such object or event to be located in a previously established chronology. This usually requires what is commonly known as a "dating method". Several dating methods exist, depending on different criteria and techniques, and some very well known examples of disciplines using such techniques are, for example, history, archaeology, geology, paleontology, astronomy and even forensic science, since in the latter it is sometimes necessary to investigate the moment in the past during which the death of a cadaver occurred. These methods are typically identified as absolute, which involves a specified date or date range, or relative, which refers to dating which places artifacts or events on a timeline relative to other events and/or artifacts. Other markers can help place an artifact or event in a chronology, such as nearby writings and stratigraphic markers. Absolute an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Feldspar
Potassium feldspar refers to a number of minerals in the feldspar group that contain large amounts of potassium in the crystal lattice. *Orthoclase (endmember formula K Al Si3 O8), an important tectosilicate mineral that forms igneous rock *Microcline, chemically the same as orthoclase, but with a different crystalline structure *Sanidine, the high-temperature form of potassium feldspar *Adularia, a more ordered low-temperature variety of orthoclase or partially disordered microcline *Amazonite Amazonite, also known as amazonstone, is a green tectosilicate mineral, a variety of the potassium feldspar called microcline. Its chemical formula is KAlSi3O8, which is Polymorphism (materials science), polymorphic to orthoclase. Its name is ta ... (sometimes called "Amazon stone"), a green variety of microcline {{SIA Feldspar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrochronology
Dendrochronology (or tree-ring dating) is the scientific method of chronological dating, dating tree rings (also called growth rings) to the exact year they were formed in a tree. As well as dating them, this can give data for dendroclimatology, the study of climate and atmospheric conditions during different periods in history from the wood of old trees. Dendrochronology derives from the Ancient Greek (), meaning "tree", (), meaning "time", and (), "the study of". Dendrochronology is useful for determining the precise age of samples, especially those that are too recent for radiocarbon dating, which always produces a range rather than an exact date. However, for a precise date of the death of the tree a full sample to the edge is needed, which most trimmed timber will not provide. It also gives data on the timing of events and rates of change in the environment (most prominently climate) and also in wood found in archaeology or works of art and architecture, such as old pane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoluminescence Dating
Thermoluminescence dating (TL) is the determination, by means of measuring the accumulated radiation dose, of the time elapsed since material containing crystalline minerals was either heated (lava, ceramics) or exposed to sunlight (sediments). As a crystalline material is heated during measurements, the process of thermoluminescence starts. Thermoluminescence emits a weak light signal that is proportional to the radiation dose absorbed by the material. It is a type of luminescence dating. The technique has wide application, and is relatively cheap at some US$300–700 per object; ideally a number of samples are tested. Sediments are more expensive to date. , University of Wollongong, Australia [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optically Stimulated Luminescence
In physics, optically stimulated luminescence (OSL) is a method for measuring doses from ionizing radiation. It is used in at least two applications: * Luminescence dating of ancient materials: mainly geological sediments and sometimes fired pottery, bricks etc., although in the latter case thermoluminescence dating is used more often * Radiation dosimetry, which is the measurement of accumulated radiation dose in the tissues of health care, nuclear, research and other workers, as well as in building materials in regions of nuclear disaster The method makes use of electrons trapped between the valence and conduction bands in the crystalline structure of certain minerals (most commonly quartz and feldspar). The trapping sites are imperfections of the lattice — impurities or defects. The ionizing radiation produces electron-hole pairs: Electrons are in the conduction band and holes in the valence band. The electrons that have been excited to the conduction band may become en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of Silicon dioxide, SiO2. Quartz is, therefore, classified structurally as a Silicate mineral#Tectosilicates, framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Technique
A scientific technique is any systematic way of obtaining information about a scientific nature or to obtain a desired material or product. Scientific techniques can be divided in many different groups, e.g.: # Preparative techniques ## Synthesis techniques, e.g. the use of Grignard reagents in organic chemistry ## Growth techniques, e.g. crystal growth or cell cultures in biology ## Purification techniques e.g. those in chemistry # Measurement techniques ## Analysis techniques, e.g. ones that reveal atomic or molecular composition. ## Characterization techniques, e.g. ones that measure a certain property of a material. ## Imaging techniques, e.g. microscopy In some cases these methods have evolved into instrumental techniques that require expensive equipment. This is particularly true in sciences like physics, chemistry, and astronomy. It is customary to abbreviate the names of techniques into acronyms, although this does not hold for all of them. Particularly the advent of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Spin Resonance
Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spins excited are those of the electrons instead of the atomic nuclei. EPR spectroscopy is particularly useful for studying metal complexes and organic radicals. EPR was first observed in Kazan State University by Soviet physicist Yevgeny Zavoisky in 1944, and was developed independently at the same time by Brebis Bleaney at the University of Oxford. Theory Origin of an EPR signal Every electron has a magnetic moment and spin quantum number s = \tfrac , with magnetic components m_\mathrm = + \tfrac or m_\mathrm = - \tfrac . In the presence of an external magnetic field with strength B_\mathrm , the electron's magnetic moment aligns itself either antiparallel ( m_\mathrm = - \tfrac ) or parallel ( m_\mathrm = + \tfrac ) to the fie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hominidae
The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic Family (biology), family of primates that includes eight Neontology#Extant taxa versus extinct taxa, extant species in four Genus, genera: ''Orangutan, Pongo'' (the Bornean orangutan, Bornean, Sumatran orangutan, Sumatran and Tapanuli orangutan); ''Gorilla'' (the Eastern gorilla, eastern and western gorilla); ''Pan (genus), Pan'' (the chimpanzee and the bonobo); and ''Homo'', of which only Human, modern humans (''Homo sapiens'') remain. Numerous revisions in classifying the great apes have caused the use of the term ''hominid'' to change over time. The original meaning of "hominid" referred only to humans (''Homo'') and their closest extinct relatives. However, by the 1990s humans and other apes were considered to be "hominids". The earlier restrictive meaning has now been largely assumed by the term ''Hominini, hominin'', which comprises all members of the human clade after the split ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
