Abstract. Analyses of thorium and uranium from deep-sea barites and their sediments show that: (1) Marine barites concentrate thorium relative to their bulk sediments and appear to be growing near the sediment surface. However, some barites are found associated with ferromanganese deposits, and these barites, like continental varieties, …Web
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The ratio of ionium to thorium varies exponentially with depths in deepsea sediments of the Pacific Ocean and gives rates of accumulation of the order of millimeters per thousand of years. Surface values of the ratio were not constant over the eastern Pacific Ocean. This observation may result from differences in thorium isotope concentrations in near …Web
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The ratio of ionium to thorium varies exponentially with depths in deepsea sediments of the Pacific Ocean and gives rates of accumulation of the order of millimeters per thousand of years. Surface … Expand. 50. Save. The Particulate Matter in the Sea as Determined by Means of the Tyndall Meter.Web
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lead derived from uranium would be expected to have a different atomic weight to ordinary lead. In 1914, ... thorium only in its atomic weight. Ionium was thus identified as an isotope of thorium (Th-230). Ellen Gleditsch and isotopes beyond the radioelements Although born and educated inWeb
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Ionium-thorium dating, method of establishing the time of origin of marine sediments according to the amount of ionium and thorium they contain. Because uranium …Web
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The general prospects of several radioisotopes are reviewed; the special properties of U/sup 232/ and Th/sup 228/ are poi nted out; and ionium (Th/sup 230/ ) and protactinium target materials are discussed from the sthndpoint of availability and chemical separations processes required for the preparation of U/ sup 232/ and Th/sup 228/.Web
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Abstract. The ionium/thorium method for determining the rates of accumulation of marine sediments has been applied to a group of deposits from the Pacific, Atlantic and Indian …Web
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The ratio of ionium to thorium varies exponentially with depths in deepsea sediments of the Pacific Ocean and gives rates of accumulation of the order of millimeters per thousand of …Web
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Climatic curves derived from variations in planktonic foraminifera in three deep-sea cores are compared with isotopic temperature curves drawn by Emiliani on the basis of the same cores. ... Environmental Science, Geology. Science. 1966; TLDR. Two cores from the eastern Pacific were analyzed faunally and dated by the ionium: thorium method and ...Web
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Turbidite-derived silty sand and clayey silt are recorded at Site 386, and volcanic sand at Site 841 (Fig. 4). Clay was present in all the major oceans (Fig. 4), but mainly concentrated in the North Pacific and South Pacific oligotrophic gyres. Site 913, on the present day East Greenland margin, is the northernmost location in the EOT …Web
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Uranium and thorium fractions are purified for electroplating by anion exchange, with elements naturally present used as carriers. Final determinations are made by α …Web
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But the most interesting point is that, if we take the atomic weight of the lead isotope derived from uranium as 206.0, and that derived from thorium as 208.0, and calculate the atomic weight of ...Web
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Thorium is a chemical element with symbol Th and atomic number 90. A radioactive actinide metal, thorium is one of only two significantly radioactive elements that still occur naturally in large quantities as a primordial element (the other being uranium). [lower-alpha 1] It was discovered in 1829 by the Norwegian amateur mineralogist Morten Thrane …Web
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The U.S. Department of Energy's Office of Scientific and Technical InformationWeb
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Abstract. Two cores from the eastern Pacific were analyzed faunally and dated by the ionium: thorium method. Comparison of the results of these and of similar studies of Atlantic cores indicate that faunal changes, representing changes between the glacial and interglacial stages of the Pleistocene, occurred in both oceans simultaneously.Web
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Ionium-thorium chronology. The method of ionium-thorium chronology (PICCIOTTO and WILCAIN, 1954) is based upon the simultaneous removal of ionium (23°Th, t~ = 80,000 years, a member of the ~3sU radioactive series) and thorium (~32Th, t½ = 1.4 x 101° years) from the overlying sea-water to one or more of the mineral components of the sediments.Web
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The validity of the ionium-thorium age method is based upon the following assumptions: (1) the ratio of thorium-230 (ionium) to thorium-232 in ocean water remains constant during the age span of the sample to be dated; (2) during precipitation there is no chemical fractionation of ionium and thorium, so that they are precipitated in a constant ratio; (3) …Web
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a system for detection of ionium, thorium, and protactinium to date deep- sea cores. full record; other ...Web
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Thorium is a(n) research topic. Over the lifetime, 3684 publication(s) have been published within this topic receiving 45201 citation(s). The topic is also known as: Th & element 90. Popular works include U-Th isotopes in arc magmas: Implications for element transfer from the subducted crust, Sequential separation of light rare-earth elements, thorium and …Web
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Journal Article: THORIUM DETERMINATION IN DEEP-SEA SEDIMENTS. THORIUM DETERMINATION IN DEEP-SEA SEDIMENTS. Full Record; Other Related Research; Authors: Picciotto, E; Wilgain, S Publication Date: Thu Apr 01 00:00:00 EST 1954 ...Web
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It is known that ionium (thorium-230) is at least partly separated from its predecessors in the ocean carried to the ocean floor, where it generally ... identified as derived from various genera ...Web
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based upon a sedimentation rate of 0.7 mm/lOOO years derived from ionium/thorium EXPERIMENTAL TECHNIQUES L measurements. Uvanium and thorium The separation techniques and the analytical methods are described for thorium isotopes in BERNAT and GOLDBERG (1969). The phillipsite samples were dissolved in HF to which were added …Web
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the nearly carrier-free thorium (ionium + uranium X,) redissolved in the smallest possible volume o a complexing solution of citric buffer at pH 7 •. The yield of ionium recovered is checked by ...Web
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Uranium series: The radioactive decay series that starts with 238 U, 235 U and 232 Th and ends with stable isotopes of 206 Pb, 207 Pb and 208 Pb, respectively. Secular equilibrium: A situation in which the quantity of a radioactive isotope remains constant because its production rate (due to decay of a parent isotope) is equal to its decay rate.Web
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The U.S. Department of Energy's Office of Scientific and Technical InformationWeb
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The formation of phillipsite continued for a little over a million years based upon a sedimentation rate of 0-7 mm/1000 years derived from ionium/thorium measurements. EXPEBDBENTAL TECHNIQUES uranium and thorium The separation techniques and the analytical methods are described for thorium isotopes in BEBNAT and GOIDBEBO (1969).Web
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Uranium–thorium dating [edit | edit source]. Uranium–thorium dating is based on the decay of 234 U to 230 Th. . 232 Th is a primordial radioisotope, but 230 Th only occurs as an intermediate decay product in the decay chain of 238 U.. Uranium–thorium dating is a relatively short-range process because of the short half …Web
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Isotopes of thorium is a(n) research topic. Over the lifetime, 601 publication(s) have been published within this topic receiving 9343 citation(s). The topic is also known as: thorium & Th. Popular works include Geochronological studies of deep sea sediments by the ionium/thorium method, 234Th:238U disequilibria within the California Current1 and more.Web
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The sedimentation rates derived from Ra and Ra/Th are comparable to those deduced from Pa, Pa/Th, and Pa/Ra. This is an indirect proof that in the sedi- ment …Web
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Geochronological studies of deep sea sediments by the ionium/thorium method @article{Goldberg1962GeochronologicalSO, title={Geochronological studies of deep sea sediments by the ionium/thorium method}, author={Edward D. Goldberg and Minoru Koide}, journal={Geochimica et Cosmochimica Acta}, year={1962}, volume={26}, …Web
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This study explores a new way of determining the age of sediments at the seafloor. It exploits the fact that a rare variety of the element thorium (230 Th) that occurs naturally in the ocean is supplied to the seafloor at a constant rate.Due to its natural radioactivity with a half-life of 75,380 years, it can be used to determine the age of …Web
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Clay mineralogy of bottom sediment in the Jinhae Bay, Korea. B. Park Sang-Joon Han Jong-Wha Lee. Geology, Environmental Science. 1976. The bottom sediments of Jinhae Bay area contain, on average, 45 % illite, 23 % kaolinite, 17 % intergrade clay, 10 % chlorite, and 5 % smectite. The geographical distribution of the clay minerals….Web
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