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Encyclopedia > Environmental radioactivity

The environmental radioactivity page is devoted to the subject of radioactive materials in man and his environment. Radioactivity may mean: Look up radioactivity in Wiktionary, the free dictionary. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (the great apes). ...

Contents


Overview

A review of the subject has been published by SCOPE in the report SCOPE 50 Radioecology after chernobyl. This report has seven main subsections. The scope of a given activity or subject is the area or range that it covers. ...

  • Sources of radioactivity
  • Case-studies of Significant Radioactive Releases (man made)
  • Atmospheric Pathways
  • Terrestrial Pathways
  • Radionuclide Aquatic Pathways
  • Behaviour and Decontamination of Artificial Radionuclides in the Urban Environment
  • Dosimetry and the Assessment of Environmental Effects of Radiation Exposure
  • Appendices
  • References and Bibliography

After release into the environment radioactive materials can reach humans in a range of different routes, the main route of concern oftein the chemistry of the element dictates the most important exposure route.

Air bourn radioactive material can have an effect on humans via a range of routes.
Air bourn radioactive material can have an effect on humans via a range of routes.

Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ...

Man made

The releases of manmade radioactivity (and NORM) into the environment can be divided into several classes.


1. Normal licensed releases which occur during normal operation of a plant or process.

  • For instance the release of 99Tc from a nuclear medicine department of a hospital which occurs when a person given a Tc imaging agent goes to the toilet.

2. Releases which occur during maloperation of a plant or process. Nuclear medicine is a branch of medicine and medical imaging that uses unsealed radioactive substances in diagnosis and therapy. ... Boeing 747 toilet A toilet is a plumbing fixture and a disposal system primarily intended for the disposal of the bodily wastes; urine, fecal matter, vomit and menses. ...

3. Releases which occur as a result of military activity. The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ...

  • For example an atomic bomb test.

4. Releases which occur as a result of a crime.

The Goiânia accident was an incident of radioactive contamination in central Brazil that killed several people and injured many others. ... Theft (also known as stealing) is, in general, the wrongful taking of someone elses property without that persons willful consent. ...

The trinity test

One dramatic source of man-made radioactivity is an atom bomb test. The glassy trinitite formed by the first atom bomb contains radioisotopes formed by neutron activation and nuclear fission. In addition some natural radioisotopes are present. A recent paper (P.P. Parekh, T.M. Semkow, M.A. Torres, D.K. Haines, J.M. Cooper, P.M. Rosenberg and M.E. Kitto, Jorunal of Environmental Radioactivity, 2006, 85, 103-120) reports the levels of long lived radioisotopes in the trinitite. The trinitite was formed from feldspar and quartz which were melted by the heat. Two samples of trinitite were used, the first (left hand side bars) was taken from between 40 and 65 meters of ground zero while the other sample was taken from further away from the ground zero point. The mushroom cloud of the atomic bombing of Nagasaki, Japan, in 1945 lifted nuclear fallout some 18 km (60,000 feet) above the epicenter. ... Sample of Trinitite. ... A radionuclide is an atom with an unstable nucleus. ... Feldspar is the name of an important group of rock-forming minerals which make up perhaps as much as 60% of the Earths crust. ... Quartz is amongst one of the most common minerals in the Earths continental crust. ... The metre, or meter (symbol: m) is the SI base unit of length. ... Ground zero is the exact location on the ground where any explosion occurs. ...

Levels of radioactivity in the trinity glass from two different samples as measured by gamma spectrscopy on lumps of the glass
Enlarge
Levels of radioactivity in the trinity glass from two different samples as measured by gamma spectrscopy on lumps of the glass

The 152Eu and 154Eu was mainly formed by the neutron activation of the europium in the soil, it is clear that the level of radioactivity for these isotopes is highest where the neutron dose to the soil was larger. Some of the 60Co is generated by activation of the cobalt in the soil, but some was also generated by the activation of the cobalt in the steel (100 foot) tower. This 60Co from the tower would have been scattered over the site reducing the difference in the soil levels. General Name, Symbol, Number europium, Eu, 63 Chemical series lanthanides Group, Period, Block ?, 6, f Appearance silvery white Atomic mass 151. ... Soil is the material on the surface of a lithosphere subject to weathering, and especially the earthy portion of that material. ... General Name, Symbol, Number cobalt, Co, 27 Chemical series transition metals Group, Period, Block 9, 4, d Appearance metallic with gray tinge Atomic mass 58. ... The old steel cable of a colliery winding tower Steel is a metal alloy whose major component is iron, with carbon being the primary alloying material. ...


The 133Ba and 241Am are due to the neutron activation of barium and plutonium inside the bomb. The barium was present in the form of the nitrate in the chemical explosives used while the plutonium was the fissile fuel used. General Name, Symbol, Number barium, Ba, 56 Chemical series alkaline earth metals Group, Period, Block 2, 6, s Appearance silvery white Atomic mass 137. ... This article or section should include material from Fissile material In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. ...


It is interesting to note that the 137Cs level is higher in the sample which was further away from the ground zero point, this is through to be because the precursors to the 137Cs (137I and 137Xe) and the cesium to a lesser degree are volitile. The natural radioisotopes in the glass are about the same in both locations.

Fallout around the Trinity site. The radioactive cloud moved towards northeast with high röntgen levels within about 100 miles (62 km).
Fallout around the Trinity site. The radioactive cloud moved towards northeast with high röntgen levels within about 100 miles (62 km).

Image File history File links Download high resolution version (1622x1329, 204 KB) Trinity test fallout over New-Mexico. ... Image File history File links Download high resolution version (1622x1329, 204 KB) Trinity test fallout over New-Mexico. ... The röntgen or roentgen (symbol R) is a unit of exposure to ionizing radiation (X or gamma rays), and is named after the German physicist Wilhelm Röntgen. ...

Activation products

The action of neutrons on stable isotopes can form radioisotopes, for instance the neutron bombardment (neutron activation) of nitrogen-14 forms carbon-14. This radioisotope can be released from the nuclear fuel cycle, this is the radioisotope responsible for the majority of the dose experienced by the population as a result of the activities of the nuclear power industry. For a discussion of the physics of neutron activation see Neutron activation analysis. Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 940 MeV/c² (1. ... Isotopes are forms of an element, therefore their nuclei have the same atomic number — the number of protons in the nucleus — but different mass numbers because they contain different numbers of neutrons. ... A radionuclide is an atom with an unstable nucleus. ... Neutron activation is the process by which neutron radiation induces radioactivity in materials. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless Atomic mass 14. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... // The nuclear fuel cycle, also called nuclear fuel chain, consists of front end steps that lead to the preparation of uranium for use as fuel for reactor operation and back end steps that are necessary to safely manage, prepare, and dispose of radioactive waste. ... A nuclear power station. ... // How Neutron Activation Analysis Works Neutron Activation Analysis (NAA) is a nuclear process used for determining certain concentrations of elements in a vast amount of materials. ...


It is interesting to note that the activities of man, nuclear bomb testing and the use of fossil fuels have increased and decreased the specific activity of carbon respectivly. See the page on Radiocarbon dating for further details. Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 to determine the age of carbonaceous materials up to ca 60,000 years. ...


Fission products

See fission products for more detail, two sources of these radioisotopes is nuclear fallout from atomic bombs and nuclear accidents such as chernobyl. To meet Wikipedias quality standards, this article or section may require cleanup. ... A radionuclide is an atom with an unstable nucleus. ... Map of hypothetical fallout dispersal after a large-scale nuclear attack against the United States. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 km (11 mi) above the epicenter. ... Chernobyl area. ...


Discharges from plants within the nuclear fuel cycle introduce fission products to the environment, the releases from nuclear reprocessing plants tend to be medium to longlived radioisotopes, this is because the nuclear fuel is allowed to cool for several years before being dissolved in the nitric acid. The releases from nuclear reactor accidents and bomb detonations will contain a greater amount of the shortlived radioisotopes (when the amounts are expressed in activity {Bq}). // The nuclear fuel cycle, also called nuclear fuel chain, consists of front end steps that lead to the preparation of uranium for use as fuel for reactor operation and back end steps that are necessary to safely manage, prepare, and dispose of radioactive waste. ... // Nuclear reprocessing separates any usable elements (e. ... Nuclear fuel is any material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned to derive energy. ... The chemical compound nitric acid (HNO3), otherwise known as aqua fortis or spirit of nitre, is a colorless, corrosive liquid, a toxic acid which can cause severe burns. ... Core of a small nuclear reactor used for research. ... BQ may mean: Areomar Airlines: IATA airline designator Bachelor quarters, in military parlance Be quiet Best Quality Best Quality furniture in [1]BQofSweden, Germany and Holland Bene quiescat, Latin for May he rest well Bicycle Queensland Bloc Québécois, a political party of Canada Broadcast quality Navassa Island: FIPS...


Short lived

An example of a shortlived fission product is Iodine-131, this can also be formed as an activation product by the neutron activation of tellurium. Iodine-131, also called radioiodine, is a radioisotope of iodine. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... General Name, Symbol, Number tellurium, Te, 52 Chemical series metalloids Group, Period, Block 16, 5, p Appearance silvery lustrous gray Atomic mass 127. ...

Per capita thyroid doses in the continental United States resulting from all exposure routes from all atmospheric nuclear tests conducted at the Nevada Test Site from 1951-1962.

Image File history File links US_fallout_exposure. ... Image File history File links US_fallout_exposure. ... Preparation for an underground nuclear test at the Nevada Test Site in the 1980s. ... November 1951 nuclear test at Nevada Test Site. ...

Medium lived

The classic example is 137Cs, the cesium is released in bomb fallout and from the nuclear fuel cycle. A paper has been written on the radioactivity found in oysters found in the Irish Sea, these were found by gamma spectrscopy to contain 141Ce, 144Ce, 103Ru, 106Ru, 137Cs, 95Zr and 95Nb. In addition a zinc activation product (65Zn) was found, this is thought to be due to the corrosion of magnox fuel cladding in cooling ponds. It is likely that the modern releases of all these isotopes from Windscale is smaller. General Name, Symbol, Number Caesium, Cs, 55 Series Alkali metals Group, Period, Block 1(IA), 6, s Density, Hardness 1879 kg/m3, 0. ... // The nuclear fuel cycle, also called nuclear fuel chain, consists of front end steps that lead to the preparation of uranium for use as fuel for reactor operation and back end steps that are necessary to safely manage, prepare, and dispose of radioactive waste. ... Crassostrea gigas, Marennes-Oléron Crassostrea gigas, Marennes-Oléron Crassostrea gigas, Marennes-Oléron, opened The name oyster is used for a number of different groups of molluscs which grow for the most part in marine or brackish water. ... Relief map of the Irish Sea. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Appearance bluish pale gray Atomic mass 65. ... Rust, the most familiar example of corrosion. ... Magnox is an obsolesent type of nuclear power reactor; When operated on a short fuel cycle (which is uneconomic) they can also produce plutonium for nuclear weapons. ... Sellafield aerial view. ...


A. Preston, J.W.R. Dutton and B.R. Harvey, Nature, 1968, 218, 689-690.


Note that a good source of data on the subject of cesium in chernobyl fallout exists at [1], this is the Ukrainian Research Institute for Agricultural Radiology. General Name, Symbol, Number Caesium, Cs, 55 Series Alkali metals Group, Period, Block 1(IA), 6, s Density, Hardness 1879 kg/m3, 0. ... Chernobyl area. ...


A great deal of cesium was released during the Goiânia accident where a radioactive source (made for medical use) was stolen and then smashed open during an attempt to convert it into scrap metal. The accident could have been stopped at several stages; first, the last legal owners of the source failed to make arrangements for the source to be stored in a safe and secure place; and second, the scrap metal workers who took it did not recognise the markings which indicated that it was a radioactive object. The Goiânia accident was an incident of radioactive contamination in central Brazil that killed several people and injured many others. ...


P. Soudek, Š. Valenová, Z. Vavříková and T. Vaněk, Journal of Environmental Radioactivity, 2006, 88, 236-250 report details of the uptake of 90Sr and 137Cs into sunflowers grown under hydroponic conditions. The cesium was found in the leaf veins, in the stem and in the apical leaves. It was found that 12% of the cesium entered the plant, and 20% of the strontium. This paper also reports details of the effect of potassium, ammonium and calcium ions on the uptake of the radioisotopes. Binomial name Helianthus annuus L. The sunflower (Helianthus annuus) is an annual plant in the Family Asteraceae, with a large flower head (inflorescence). ... Hydroponics is the growing of plants without soil. ... Apical, from the Latin APEX (plural apices), meaning to be at the apex or tip, has a number of meanings. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ... Fumes from hydrochloric acid and ammonia forming a white cloud of ammonium chloride Ammonium is also an old name for the Siwa oasis in western Egypt. ... General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Atomic mass 40. ...


Note that cesium binds tightly to clay minerals such as illite and montmorillonite hence it remains in the upper layers of soil where it can be accessed by plants with shallow roots (such as grass). Hence grass and mushrooms can carry a considerable amount of 137Cs which can be transferred to humans through the food chain. One of the best countermeasures in dairy farming against 137Cs is to mix up the soil by deeply ploughing the soil. This has the effect of putting the 137Cs out of reach of the shallow roots of the grass, hence the level of radioactivity in the grass will be lowered. Also after a nuclear war or serious accident the removal of top few cm of soil and its burial in a shallow trench will reduce the long term gamma dose to humans due to 137Cs as the gamma photons will be attenuated by their passage through the soil. The more remote the trench is from humans and the deeper the trench is the better the degree of protection which will be afforded to the human population. The Gay Head cliffs in Marthas Vineyard are made almost entirely of natural clays. ... Structure of Illite mica - USGS. Illite is a non-expanding, clay-sized, micaceous mineral. ... Montmorillonite is a very soft phyllosilicate mineral that typically forms in microscopic crystals, forming a clay. ... An area of grass-like plants Grass generally describes a monocotyledonous green plant characterized by slender leaves, called blades, which usually grow arching upwards from the ground. ... Basidiocarps (mushrooms) of the fungus Leucocoprinus sp. ... Food chains and food webs or food networks describe the feeding relationships between so the plank species in a biotic community. ... For the constellation known as The Plough see Ursa Major. ... Primary and secondary roots in a cotton plant In vascular plants, the root is that organ of a plant body that typically lies below the surface of the soil (compare with stem). ... Soil is the material on the surface of a lithosphere subject to weathering, and especially the earthy portion of that material. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (the great apes). ... In quantum physics, the photon (from Greek φως, phōs, meaning light) is the quantum of the electromagnetic field (light). ... Soil is the material on the surface of a lithosphere subject to weathering, and especially the earthy portion of that material. ...


In livestock farming an important countermeasure against 137Cs is to feed to animals a little prussian blue. This iron potassium cyanide compound acts as a ion-exchanger. The cyanide is so tightly bonded to the iron that it is safe for a human to eat several grams of prussian blue per day. The prussian blue reduces the biological half life (different from the nuclear half life) of the cesium. The physical or nuclear half life of 137Cs is about 30 years. This is a constant which can not be changed but the biological half life is not a constant. It will change according to the nature and habits of the organism it is expressed for. Cesium in humans normally has a biological half life of between one and four months. An added advantage of the prussian blue is that the cesium which is stripped from the animal in the droppings is in a form which is not available to plants. Hence it prevents the cesium from being recycled. The form of prussian blue required for the treatment of humans or animals is a special grade. Attempts to use the pigment grade used in paints have not been successful. Sheep are commonly bred as livestock. ... A sample of Prussian blue Prussian blue (Preußisch Blau, Berliner Blau) is a dark blue pigment used in paints and formerly in blueprints. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ... A space-filling model of the cyanide ion A cyanide is any chemical compound that contains the cyano group -C≡N, with the carbon atom triple-bonded to the nitrogen atom. ... Ion exchange is a process in which ions are exchanged between a solution and an ion exchanger, an insoluble solid or gel. ... The biological halflife of a substance is the time required for half of that substance to be removed from an organism by either a physical or a chemical process. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... General Name, Symbol, Number Caesium, Cs, 55 Series Alkali metals Group, Period, Block 1(IA), 6, s Density, Hardness 1879 kg/m3, 0. ... Rabbit feces are usually 8-10 mm in diameter, dry to the touch, and look similar to a Raisinette candy. ... In biology, pigment is any material resulting in color in plant or animal cells which is the result of selective absorption. ... Dried green paint Paint is the general term for a family of products used to protect and add color to an object or surface by covering it with a pigmented coating. ...


Long lived

A pair of good examples would be iodine-129 and Tc-99. General Name, Symbol, Number iodine, I, 53 Chemical series halogens Group, Period, Block 17, 5, p Appearance violet-dark gray, lustrous Atomic mass 126. ...


Plutonium and the other actinides

In popular culture plutonium is credited with being the ultimate threat to life and limb which is wrong; while ingesting plutonium is not likely to be good for one's health, other radioisotopes such as radium are more toxic to humans. Regardless, the introduction of the transuranium elements such as plutonium into the environment should be avoided wherever possible. Currently the activities of the nuclear reprocessing industry have been subject to great debate as one of the fears of those opposed to the industry is that large amounts of plutonium will be either mismanaged or released into the environment. In the past one of the biggest releases of plutonium into the environment has been nuclear bomb testing. General Name, Symbol, Number radium, Ra, 88 Chemical series alkaline earth metals Group, Period, Block 2, 7, s Appearance silvery white metallic Atomic mass (226) g/mol Electron configuration [Rn] 7s2 Electrons per shell 2, 8, 18, 32, 18, 8, 2 Physical properties Phase solid Density (near r. ... General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass (244) g/mol Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ... // Nuclear reprocessing separates any usable elements (e. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, in 1945 lifted nuclear fallout some 18 km (60,000 feet) above the epicenter. ...

  • Those tests in the air scattered some plutonium over the entire globe; this great dilution of the plutonium has resulted in the threat to each exposed person being very small as each person is only exposed to a very small amount.
  • The underground tests tend to form molten rock which rapidly cools and seals in the actinides so rendering them unable to move, again the threat to humans is small unless the site of the test is dug up.
  • The safety trials where bombs were subject to simulated accidents pose the greatest threat to people; some areas of land used for such experiments (conducted in the open air) have not been fully released for general use despite in one case an extensive decontamination.

For further details see actinides in the environment. This article about actinides in the environment is about the sources, environmental behaviour and effects of actinides in the environment. ...


Natural

Activation products from cosmic rays

Cosmogenic isotopes (or cosmogenic nuclides) are rare isotopes created when a high-energy cosmic ray interacts with the nucleus of an in situ atom. These isotopes are produced within earth materials such as rocks or soil, in Earth's atmosphere, and in extraterrestrial items such as meteorites. By measuring cosmogenic isotopes, scientists are able to gain insight into a range of geological and astronomical processes. There are both radioactive and stable cosmogenic isotopes. These radioisotopes such as tritium, carbon-14 and phosphorus-32. Isotopes are forms of an element, therefore their nuclei have the same atomic number — the number of protons in the nucleus — but different mass numbers because they contain different numbers of neutrons. ... Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ... A semi-accurate depiction of the helium atom. ... In situ (in place in Latin), a term used in: biology, where it means to examine the phenomenon exactly in place where it occurs (without removing it in some special medium etc. ... Properties In chemistry and physics, an atom (Greek άτομον meaning indivisible) is the smallest possible particle of a chemical element that retains its chemical properties. ... Sedimentary, volcanic, plutonic, metamorphic rock types of North America. ... Soil is the material on the surface of a lithosphere subject to weathering, and especially the earthy portion of that material. ... Earth (often referred to as The Earth) is the third planet in the solar system in terms of distance from the Sun, and the fifth in order of size. ... Layers of Atmosphere (NOAA) Air redirects here. ... A meteorite is an extraterrestrial body that survives its impact with the Earths surface without being destroyed. ... The physicist Albert Einstein is probably historys most widely recognized scientist. ... The Blue Marble: The famous photo of the Earth taken en route to the Moon by Apollo 17s Harrison Schmitt on December 7, 1972. ... Radio telescopes are among many different tools used by astronomers Astronomy (Greek: αστρονομία = άστρον + νόμος, astronomia = astron + nomos, literally, law of the stars) is the science of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as auroras and cosmic background radiation). ... A radionuclide is an atom with an unstable nucleus. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Tritium (symbol T or 3H) is a radioactive isotope of hydrogen. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... This article is about the chemical element. ...


Production modes

Here is a list of radioisotopes formed by the action of cosmic rays on the atomosphere, the list also contains the production mode of the isotope. This data was obtained from the SCOPE50 report, see table 1.9 of chapter 1 Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ...

Isotopes formed by the action of cosmic rays on the air
Isotope Mode of formation
3H (tritium) 14N(n, 12C)3H
7Be Spallation (N and O)
10Be Spallation (N and O)
11C Spallation (N and O)
14C 14N(n, p) 14C
18F 18O(p, n)18F and Spallation (Ar)
22Na Spallation (Ar)
24Na Spallation (Ar)
28Mg Spallation (Ar)
31Si Spallation (Ar)
32Si Spallation (Ar)
32P Spallation (Ar)
34mCl Spallation (Ar)
35S Spallation (Ar)
36Cl 35Cl(n, )36Cl
37Ar 37Cl(p, n)37Ar
38Cl Spallation (Ar)
38S Spallation (Ar)
39Ar 38Ar(n, )39Ar
39Cl 40Ar(n, np)39Cl & spallation (Ar)
41Ar 40Ar(n, )41Ar
81Kr 80Kr(n, ) 81Kr

Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ...

Transfer to ground

It is interesting to note that the level of berylium-7 in the air is related to the sun spot cycle, as radiation from the sun forms this radioisotope in the atmosphere. The rate at which it is transferred from the air to the ground is controlled in part by the weather. Sun SPOT (Sun Small Programmable Object Technology) is a wireless sensor network (WSN) mote developed by Sun Microsystems. ... A radionuclide is an atom with an unstable nucleus. ...

The rate of delivery of Be-7 from the air to the ground in Japan (source M. Yamamoto et. al., Journal of Environmental Radioactivity, 2006, 86, 110-131)
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The rate of delivery of Be-7 from the air to the ground in Japan (source M. Yamamoto et. al., Journal of Environmental Radioactivity, 2006, 86, 110-131)

Applications in geology listed by isotope

Commonly measured long lived cosmogenic isotopes
element mass half-life (years) typical application
helium 3 - stable - exposure dating of olivine-bearing rocks
beryllium 10 1.51 million exposure dating of quartz-bearing rocks, sediment, dating of ice cores, measurement of erosion rates
carbon 14 5,730 dating of organic matter, water
neon 21 - stable - dating of very stable, long-exposed surfaces, including meteorites
aluminum 26 720,000 exposure dating of rocks, sediment
chlorine 36 308,000 exposure dating of rocks, groundwater tracer
calcium 41 103,000 exposure dating of carbonate rocks
iodine 129 15.7 million groundwater tracer

A chemical element, often called simply element, is a chemical substance that cannot be decomposed or transformed into other chemical substances by ordinary chemical methods. ... The atomic mass of a chemical element is the mass of an atom at rest, most often expressed in unified atomic mass units. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... Olivine The mineral olivine is a magnesium iron silicate with the formula (Mg,Fe)2SiO4 in which the ratio of magnesium and iron varies between the two endmembers of the series: forsterite (Mg-rich) and fayalite (Fe-rich). ... General Name, Symbol, Number beryllium, Be, 4 Chemical series alkaline earth metals Group, Period, Block 2, 2, s Appearance white-gray metallic Atomic mass 9. ... Quartz is amongst one of the most common minerals in the Earths continental crust. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 to determine the age of carbonaceous materials up to ca 60,000 years. ... General Name, Symbol, Number neon, Ne, 10 Chemical series noble gases Group, Period, Block 18, 2, p Appearance colorless Atomic mass 20. ... A meteorite is an extraterrestrial body that survives its impact with the Earths surface without being destroyed. ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... General Name, Symbol, Number chlorine, Cl, 17 Chemical series halogens Group, Period, Block 17, 3, p Appearance yellowish green Atomic mass 35. ... Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of geologic formations. ... General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Atomic mass 40. ... Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. ... General Name, Symbol, Number iodine, I, 53 Chemical series halogens Group, Period, Block 17, 5, p Appearance violet-dark gray, lustrous Atomic mass 126. ...

Applications of dating

Because cosmogenic isotopes have long half-lives (anywhere from thousands to millions of years), scientists find them useful for geologic dating. Cosmogenic isotopes are produced at or near the surface of the Earth, and thus are commonly applied to problems of measuring ages and rates of geomorphic and sedimentary events and processes. Half-Life is a science fiction first-person shooter computer game developed by Valve Software and published by Sierra Studios in 1998, based on a heavily-modified Quake game engine. ... Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. ... Surface of the Earth Geomorphology is the study of landforms, including their origin and evolution, and the processes that shape them. ... Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of water or other liquid. ...


Specific applications of cosmogenic isotopes include:

Aletsch glacier, Switzerland A glacier is a large, long-lasting river of ice that is formed on land and moves in response to gravity. ... Bedrock is the native consolidated rock underlying the Earths surface. ... Old fault exposed by roadcut near Harrisburg, Pennsylvania. ... In geology, an escarpment is a transition zone between different physiogeographic provinces that involves an elevation differential, often involving high cliffs. ... Landslide of soil and regolith in Pakistan A landslide is a geological phenomenon which includes a wide range of ground movement, such as rock falls, deep failure of slopes, and shallow debris flows, see flow. ... Severe soil erosion in a wheat field near Washington State University, USA. Erosion s the displacement of solids (soil, mud, rock and other particles) by the agents of wind, water or ice, by downward or down-slope movement in response to gravity or by living organisms (in the case of... Absolute dating is the process of determining a specific archaeological date. ... Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 to determine the age of carbonaceous materials up to ca 60,000 years. ...

Methods of measurement for the long lived isotopes

To measure cosmogenic isotopes produced within solid earth materials, such as rock, samples are generally first put through a process of mechanical separation. The sample is crushed and desirable material, such as a particular mineral (quartz in the case of Be-10), is separated from non-desirable material by using a density separation in a heavy liquid media such as LST (lithium sodium tungstate). Quartz is amongst one of the most common minerals in the Earths continental crust. ...


The sample is then dissolved, a common isotope carrier added (Be-9 carrier in the case of Be-10), and the aqueous solution is purified down to an oxide or other pure solid.


Finally, the ratio of the rare cosmogenic isotope to the common isotope is measured using accelerator mass spectrometry. The original concentration of cosmogenic isotope in the sample is then calculated using the measured isotopic ratio, the mass of the sample, and the mass of carrier added to the sample. A 1960s single stage 2MeV linear Van de Graaff accelerator, here opened for maintenance A particle accelerator is a device that uses electric and/or magnetic fields to propel electrically charged particles to high speeds. ... Basic schematic of mass spectrometry Mass spectrometry is an analytical technique used to measure the mass-to-charge ratio of ions. ...


References about cosmogenic isotope dating

  • Gosse, John C., and Phillips, Fred M. (2001). "Terrestrial in situ cosmogenic nuclides: Theory and application". Quaternary Science Reviews 20, 1475-1560.
  • Granger, Darryl E., Fabel, Derek, and Palmer, Arthur N. (2001). "Pliocene-Pleistocene incision of the Green River, Kentucky, determined from radioactive decay of cosmogenic 26Al and 10Be in Mammoth Cave sediments". Geological Society of America Bulletin 113 (7), 825-836.

External links

Radium and Radon from the decay of long lived actinides

Radium and radon are in the environment because they are decay products of uranium and thorium. For further details about thorium see actinides in the environment, for further details of uranium see uranium in the environment while for further details about radium and radon please see radium in the environment. General Name, Symbol, Number radium, Ra, 88 Chemical series alkaline earth metals Group, Period, Block 2, 7, s Appearance silvery white metallic Atomic mass (226) g/mol Electron configuration [Rn] 7s2 Electrons per shell 2, 8, 18, 32, 18, 8, 2 Physical properties Phase solid Density (near r. ... General Name, Symbol, Number radon, Rn, 86 Chemical series noble gases Group, Period, Block 18, 6, p Appearance colorless Atomic mass (222) g/mol Electron configuration [Xe] 4f14 5d10 6s2 6p6 Electrons per shell 2, 8, 18, 32, 18, 8 Physical properties Phase gas Melting point 202 K (-71 °C... General Name, Symbol, Number uranium, U, 92 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery gray metallic; corrodes to a spalling black oxide coat in air Atomic mass 238. ... General Name, Symbol, Number thorium, Th, 90 Chemical series Actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass 232. ... This article about actinides in the environment is about the sources, environmental behaviour and effects of actinides in the environment. ... // Radium Radium in quack medicine See the story of Eben Byers for details of one very nasty case which involved a product called Radithor this contained 1 mCi of 226Ra and 1 mCi of 228Ra per bottle. ...


The radon (222Rn) released into the air decays to 210Pb and other radioisotopes, the levels of 210Pb can be measured. It is important to note that the rate of deposition of this radioisotope is very dependent on the weather. Here is a graph of the deposition rate observed in Japan (M. Yamamoto et. al., Journal of Environmental Radioactivity, 2006, 86, 110-131). General Name, Symbol, Number lead, Pb, 82 Chemical series poor metals Group, Period, Block 14, 6, p Appearance bluish white Atomic mass 207. ...

Lead-210 deposition rate as a function of time as observed in Japan

Uranium / lead dating

The uranium-lead radiometric dating scheme is one of the oldest available, as well as one of the most highly respected. It has been refined to the point that the error in dates of rocks about three billion years old is no more than two million years.


Uranium-lead dating is usually performed on the mineral zircon (ZrSiO4), though it can be used on other materials. Zircon incorporates uranium atoms into its crystalline structure as substitutes for zirconium, but strongly rejects lead. It has a very high blocking temperature, is resistant to mechanical weathering and is very chemically inert. Zircon also forms multiple crystal layers during metamorphic events, which each may record an isotopic age of the event. These can be dated by a SHRIMP ion microprobe. General Name, Symbol, Number uranium, U, 92 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery gray metallic; corrodes to a spalling black oxide coat in air Atomic mass 238. ... General Name, Symbol, Number lead, Pb, 82 Chemical series poor metals Group, Period, Block 14, 6, p Appearance bluish white Atomic mass 207. ... Zircon is a mineral belonging to the group of nesosilicates. ... Properties In chemistry and physics, an atom (Greek άτομον meaning indivisible) is the smallest possible particle of a chemical element that retains its chemical properties. ... General Name, Symbol, Number zirconium, Zr, 40 Chemical series transition metals Group, Period, Block 4, 5, d Appearance silvery white Atomic mass 91. ... An ion is an atom, group of atoms, or subatomic particle with a net electric charge. ...


One of its great advantages is that any sample provides two clocks, one based on uranium-235's decay to lead-207 with a half-life of about 700 million years, and one based on uranium-238's decay to lead-206 with a half-life of about 4.5 billion years, providing a built-in crosscheck that allows accurate determination of the age of the sample even if some of the lead has been lost. Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ...


Please for further details see radiometric dating and exponential decay. Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. ... It has been suggested that half-life be merged into this article or section. ...


Further reading

Radioactivity, Ionizing Radiation and Nuclear Energy, by J. Hala and J.D. Navratil

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