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Статті в журналах з теми "Apatite Helium"

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Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 28 січня 2023

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1

Cherniak, D. J., E. B. Watson, and J. B. Thomas. "Diffusion of helium in zircon and apatite." Chemical Geology 268, no. 1-2 (October 2009): 155–66. http://dx.doi.org/10.1016/j.chemgeo.2009.08.011.

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2

Zeitler, Peter K., Eva Enkelmann, Jay B. Thomas, E. Bruce Watson, Leonard D. Ancuta, and Bruce D. Idleman. "Solubility and trapping of helium in apatite." Geochimica et Cosmochimica Acta 209 (July 2017): 1–8. http://dx.doi.org/10.1016/j.gca.2017.03.041.

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3

Wolf, R. A., K. A. Farley, and L. T. Silver. "Helium diffusion and low-temperature thermochronometry of apatite." Geochimica et Cosmochimica Acta 60, no. 21 (November 1996): 4231–40. http://dx.doi.org/10.1016/s0016-7037(96)00192-5.

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4

Shuster, D. L., R. M. Flowers, and K. A. Farley. "Radiation damage and helium diffusion kinetics in apatite." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A590. http://dx.doi.org/10.1016/j.gca.2006.06.1094.

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5

Idleman, Bruce D., Peter K. Zeitler, and Kalin T. McDannell. "Characterization of helium release from apatite by continuous ramped heating." Chemical Geology 476 (January 2018): 223–32. http://dx.doi.org/10.1016/j.chemgeo.2017.11.019.

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6

Farley, K. A. "Helium diffusion from apatite: General behavior as illustrated by Durango fluorapatite." Journal of Geophysical Research: Solid Earth 105, B2 (February 10, 2000): 2903–14. http://dx.doi.org/10.1029/1999jb900348.

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7

House, M. A., K. A. Farley, and D. Stockli. "Helium chronometry of apatite and titanite using Nd-YAG laser heating." Earth and Planetary Science Letters 183, no. 3-4 (December 2000): 365–68. http://dx.doi.org/10.1016/s0012-821x(00)00286-7.

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8

Willett, Chelsea D., Matthew Fox, and David L. Shuster. "A helium-based model for the effects of radiation damage annealing on helium diffusion kinetics in apatite." Earth and Planetary Science Letters 477 (November 2017): 195–204. http://dx.doi.org/10.1016/j.epsl.2017.07.047.

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9

Gautheron, Cécile, Rosella Pinna-Jamme, Alexis Derycke, Floriane Ahadi, Caroline Sanchez, Frédéric Haurine, Gael Monvoisin, et al. "Technical note: Analytical protocols and performance for apatite and zircon (U–Th) ∕ He analysis on quadrupole and magnetic sector mass spectrometer systems between 2007 and 2020." Geochronology 3, no. 1 (June 1, 2021): 351–70. http://dx.doi.org/10.5194/gchron-3-351-2021.

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Abstract. Apatite and zircon (U–Th) / He thermochronological data are obtained through a combination of crystal selection, He content measurement by crystal heating with analysis using noble gas mass spectrometry, and measurement of U, Th, and Sm contents by crystal dissolution as well as solution analysis using inductively coupled plasma mass spectrometry (ICP-MS). This contribution documents the methods for helium thermochronology used at the GEOPS laboratory, Paris-Saclay University, between 2007 and the present that allow apatite and zircon (U–Th) / He data to be obtained with precision. More specifically, we show that the He content can be determined with precision (at 5 %) and accuracy using a calibration of the He sensitivity based on the Durango apatite, and its use also appears crucial to check for He and U–Th–Sm analytical problems. The Durango apatite used as a standard is therefore a suitable mineral to perform precise He calibration and yields (U–Th) / He ages of 31.1 ± 1.4 Ma with an analytical error of less than 5 % (1σ). The (U–Th) / He ages for the Fish Canyon Tuff zircon standard yield a dispersion of about 9 % (1σ) with a mean age of 27.0 ± 2.6 Ma, which is comparable to other laboratories. For the long-term quality control of the (U–Th) / He data, attention is paid to evaluating the drift of He sensitivity and blanks through time as well as that of (U–Th) / He ages and Th / U ratios (with Sm / Th when possible), all relying on the use of Durango apatite and Fish Canyon Tuff zircon as standards.

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10

Murray, Kendra E., Devon A. Orme, and Peter W. Reiners. "Effects of U–Th-rich grain boundary phases on apatite helium ages." Chemical Geology 390 (December 2014): 135–51. http://dx.doi.org/10.1016/j.chemgeo.2014.09.023.

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11

Shuster, David L., Rebecca M. Flowers, and Kenneth A. Farley. "The influence of natural radiation damage on helium diffusion kinetics in apatite." Earth and Planetary Science Letters 249, no. 3-4 (September 2006): 148–61. http://dx.doi.org/10.1016/j.epsl.2006.07.028.

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12

Lippolt, Hans Joachim, Markus Leitz, Rolf Stephan Wernicke, and Birgit Hagedorn. "(Uranium + thorium)/helium dating of apatite: experience with samples from different geochemical environments." Chemical Geology 112, no. 1-2 (January 1994): 179–91. http://dx.doi.org/10.1016/0009-2541(94)90113-9.

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13

House, Martha A., Kenneth A. Farley, and Barry P. Kohn. "An empirical test of helium diffusion in apatite: borehole data from the Otway basin, Australia." Earth and Planetary Science Letters 170, no. 4 (July 1999): 463–74. http://dx.doi.org/10.1016/s0012-821x(99)00120-x.

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14

Shuster, David L., and Kenneth A. Farley. "The influence of artificial radiation damage and thermal annealing on helium diffusion kinetics in apatite." Geochimica et Cosmochimica Acta 73, no. 1 (January 2009): 183–96. http://dx.doi.org/10.1016/j.gca.2008.10.013.

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15

Recanati, Alice, Cécile Gautheron, Jocelyn Barbarand, Yves Missenard, Rosella Pinna-Jamme, Laurent Tassan-Got, Andy Carter, et al. "Helium trapping in apatite damage: Insights from (U-Th-Sm)/He dating of different granitoid lithologies." Chemical Geology 470 (October 2017): 116–31. http://dx.doi.org/10.1016/j.chemgeo.2017.09.002.

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16

McDannell, Kalin T., and Rebecca M. Flowers. "Vestiges of the Ancient: Deep-Time Noble Gas Thermochronology." Elements 16, no. 5 (October 1, 2020): 325–30. http://dx.doi.org/10.2138/gselements.16.5.325.

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Ancient rocks have survived plate tectonic recycling for billions of years, but key questions remain about how and when they were exhumed to the surface. Constraining exhumation histories over long timescales is a challenge because much of the rock record has been lost to erosion. Argon and helium noble gas thermochronology can reconstruct deep-time <350 °C thermal histories by using the distinct temperature sensitivities of minerals such as feldspar, zircon, and apatite, while exploiting grain size and radiation damage effects on diffusion kinetics. Resolution of unique time–temperature paths over long timescales requires multiple chronometers, appropriate kinetic models, and inverse simulation techniques to fully explore and constrain possible solutions. Results suggest that surface histories of ancient continental interiors are far from uninteresting and may merely be misunderstood.

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17

Spiegel, C., B. Kohn, R. Donelick, D. Belton, A. Raza, and A. Gleadow. "The effect of long-term low-temperature exposure on fission track stability and helium diffusion in apatite." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A607. http://dx.doi.org/10.1016/j.gca.2006.06.1126.

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18

Willett, Chelsea D., Matthew Fox, and David L. Shuster. "Corrigendum to “A helium-based model for the effects of radiation damage annealing on helium diffusion kinetics in apatite” [Earth Planet. Sci. Lett. 477 (2017) 195–204]." Earth and Planetary Science Letters 481 (January 2018): 420. http://dx.doi.org/10.1016/j.epsl.2017.11.017.

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19

Idleman, Bruce D., Peter K. Zeitler, and Kalin T. McDannell. "Corrigendum to “Characterization of helium release from apatite by continuous ramped heating” [CHEMGE: 476, 5 January 2018; 223-232]." Chemical Geology 481 (March 2018): 165. http://dx.doi.org/10.1016/j.chemgeo.2018.02.006.

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20

Xu, Qiuchen, Nansheng Qiu, Wen Liu, Anjiang Shen, Xiaofang Wang, and Guangwu Zhang. "Characteristics of the temperature–pressure field evolution of Middle Permian system in the northwest of Sichuan Basin." Energy Exploration & Exploitation 36, no. 4 (January 16, 2018): 705–26. http://dx.doi.org/10.1177/0144598717752148.

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The Sichuan Basin is one of the richest oil and gas basins in China. The Middle Permian units (the Qixia and Maokou Formations) in the northwest Sichuan Basin have great potential for gas exploration. A new thermal history was reconstructed using the integrated thermal indicators of apatite and zircon (uranium–thorium)/helium ages, zircon fission tracks, and vitrinite reflectance data. The modeled results indicated that the northwest Sichuan Basin experienced gradual cooling, during which the heat flow at Middle Permian time (70–90 mW/m2) decreased to its current level of approximately 50 mW/m2. This study used basin modeling to reconstruct the paleo-pressure, which showed that the Middle Permian in the northwest Sichuan Basin generally developed overpressure. The pressure evolution of the Middle Permian can be divided into three stages: (1) a slight overpressure stage (T2–T3), (2) an intensive overpressure stage (J1–K2), and (3) an overpressure reduction stage (K2–present). Oil cracking and rapid tectonic subsidence are key factors that affect overpressure. The evolution of temperature–pressure has great significance with respect to hydrocarbon accumulation.

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21

Botor, Dariusz. "Tectono-thermal Evolution of the Lower Paleozoic Petroleum Source Rocks in the Southern Lublin Trough: Implications for Shale Gas Exploration from Maturity Modelling." E3S Web of Conferences 35 (2018): 02002. http://dx.doi.org/10.1051/e3sconf/20183502002.

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The Lower Paleozoic basins of eastern Poland have recently been the focus of intensive exploration for shale gas. In the Lublin Basin potential unconventional play is related to Lower Silurian source rocks. In order to assess petroleum charge history of these shale gas reservoirs, 1-D maturity modeling has been performed. In the Łopiennik IG-1 well, which is the only well that penetrated Lower Paleozoic strata in the study area, the uniform vitrinite reflectance values within the Paleozoic section are interpreted as being mainly the result of higher heat flow in the Late Carboniferous to Early Permian times and ~3500 m thick overburden eroded due to the Variscan inversion. Moreover, our model has been supported by zircon helium and apatite fission track dating. The Lower Paleozoic strata in the study area reached maximum temperature in the Late Carboniferous time. Accomplished tectono-thermal model allowed establishing that petroleum generation in the Lower Silurian source rocks developed mainly in the Devonian – Carboniferous period. Whereas, during Mesozoic burial, hydrocarbon generation processes did not develop again. This has negative influence on potential durability of shale gas reservoirs.

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22

Riebe, Clifford S., Leonard S. Sklar, Claire E. Lukens, and David L. Shuster. "Climate and topography control the size and flux of sediment produced on steep mountain slopes." Proceedings of the National Academy of Sciences 112, no. 51 (November 16, 2015): 15574–79. http://dx.doi.org/10.1073/pnas.1503567112.

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Weathering on mountain slopes converts rock to sediment that erodes into channels and thus provides streams with tools for incision into bedrock. Both the size and flux of sediment from slopes can influence channel incision, making sediment production and erosion central to the interplay of climate and tectonics in landscape evolution. Although erosion rates are commonly measured using cosmogenic nuclides, there has been no complementary way to quantify how sediment size varies across slopes where the sediment is produced. Here we show how this limitation can be overcome using a combination of apatite helium ages and cosmogenic nuclides measured in multiple sizes of stream sediment. We applied the approach to a catchment underlain by granodiorite bedrock on the eastern flanks of the High Sierra, in California. Our results show that higher-elevation slopes, which are steeper, colder, and less vegetated, are producing coarser sediment that erodes faster into the channel network. This suggests that both the size and flux of sediment from slopes to channels are governed by altitudinal variations in climate, vegetation, and topography across the catchment. By quantifying spatial variations in the sizes of sediment produced by weathering, this analysis enables new understanding of sediment supply in feedbacks between climate, tectonics, and mountain landscape evolution.

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23

He, John J. Y., and Peter W. Reiners. "A revised alpha-ejection correction calculation for (U–Th) ∕ He thermochronology dates of broken apatite crystals." Geochronology 4, no. 2 (October 27, 2022): 629–40. http://dx.doi.org/10.5194/gchron-4-629-2022.

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Abstract. Accurate corrections for the effects of alpha ejection (the loss of daughter He near grain or crystal surfaces due to long alpha stopping distances) are central to (U-Th)/He thermochronometry. In the case of apatite (U-Th)/He dating, alpha-ejection correction is complicated by the fact that crystals are often broken perpendicular to the c axis. In such cases, the correction should account for the fact that only some parts of the crystal are affected by alpha ejection. A common current practice to account for such broken crystals is to modify measured lengths of broken crystals missing one termination by a factor of 1.5, and those missing both terminations by a factor of 2. This alpha-ejection “correction correction” systematically overestimates the actual fraction of helium lost to alpha ejection, and thus overcorrects the measured date relative to that determined for an otherwise equivalent unbroken crystal. The ratio of the alpha-ejection-affected surface area to the volume of a fragmented crystal is equivalent to the surface-area-to-volume ratio of an unbroken crystal that is either twice as long (for fragments with one termination) or infinitely long (for fragments with no termination). We suggest that it is appropriate to revise the fragmentation correction to multiply the lengths of crystals missing one c-axis termination by 2, and those missing both c-axis terminations by some large number ≳20. We examine the effect of this revised correction and demonstrate the accuracy of the new method using synthetic datasets. Taking into account alpha ejection, the rounding of the He concentration profile due to diffusive loss, and the accumulation of radiation damage over a range of thermal histories, we show that the revised fragmentation alpha-ejection correction proposed here accurately approximates the corrected date of an unbroken crystal (“true” date) to within <0.7 % on average (±4.2 %, 1σ), whereas the former method overcorrects dates to be ∼3 % older than the “true” date on average. For individual grains, the former method can result in dates that are older by a few percent in most cases, and by as much as 12 % for grains with aspect ratios of up to 1:1. The revised alpha-ejection correction proposed here is both more accurate and more precise than the previous correction, and does not introduce any significant systematic bias into the apparent dates from a sample.

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24

Botor, Dariusz. "Timing of coalification of the upper carboniferous sediments in the upper silesia coal basin on the basis of by apatite fission track and helium dating." Gospodarka Surowcami Mineralnymi - Mineral Resources Management 30, no. 1 (March 1, 2014): 85–103. http://dx.doi.org/10.2478/gospo-2014-0010.

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Streszczenie Przeprowadzono datowania za pomocą metody trakowej i helowej dla apatytów z utworów karbońskich w Górnośląskim Zagłębiu Węglowym w celu określenia ram czasowych procesów uwęglcnia. Pomierzone centralne wieki trakowe apatytów mieszczą się w przedziale od 259±11 (późny perm) do 103±6 milionów lat (wczesna kreda), a średnia długość traków waha się od 11,7±0,2 do 13,7±0,1 (im. Wszystkie wieki trakowe są młodsze od wieku stratygraficznego analizowanych próbek, wskazując znaczne zaawansowanie procesów diagcnctycznych. Próbki z zachodniej i środ- kowej części GZW mają wieki trakowe od późnego permu do środkowego/późnego triasu (259±11 do 214±10 min lat). Jcdnomodalnc rozkłady długości traków i ich średnie wartości wskazują na poje- dyncze, względnie szybkie zdarzenie postwaryscyjskicgo wychładzania do temperatury poniżej 60°C, co jest zgodne zc znaczną erozją postinwersyjną utworów gómokarbońskich po fazie asturyjskicj. W pozostałej części mczozoiku następowało wolniejsze wychładzanie. Próbki zc wschodniej i NE części GZW mają wieki trakowe od późnego triasu do wczesnej kredy (210±10 do 103±6 milionów lat). Charakteryzuje je względnie krótsza średnia długość traków i wyższe odchylenia standardowe, a także w przypadku części próbek bimodalny i/lub mieszany charakter rozkładów długości. Jest to razem wskazówką bardziej złożonej historii termicznej, z długim okresem przebywania w PAZ i możliwym drugim zdarzeniem termicznym. Wieki helowe apatytów w całym basenie są wczcs- nokredowc(144,l±l 1 do 108,1±8 milionów lat), wskazując raczej na wolne postwaryscyjskic wychła- dzanie lub możliwe mczozoicznc podgrzanie karbonu do temperatury nic większej niż 60-70°C, które spowodowało częściową dyfuzję helu i odmłodzenie wieków helowych, ale równocześnie nic spo- wodowało znaczącego zabliźniania traków na większości obszaru GZW. Jedynie w NE części GZW podgrzanie mczozoicznc mogło być nieco wyższe, do temperatury 70-85°C, powodując odmłodzenie wieków trakowych, zwłaszcza przy długim okresie przebywania w PAZ. Mczozoiczny impuls ter- miczny był przypuszczalnie spowodowany cyrkulacją gorących roztworów związaną z procesami ekstensji. Powyższe zakresy temperatur i czas ich występowania świadczą, żc uwęglenie materii organicznej w GZW nastąpiło zasadniczo z końcem okresu karbońskiego.

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25

Mikhalko, Evgenya, and Evgeny Maurchev. "A mobile complex to record several secondary cosmic rays components." E3S Web of Conferences 127 (2019): 02001. http://dx.doi.org/10.1051/e3sconf/201912702001.

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The paper presents a research of the different components variations of the secondary cosmic rays (SCR). These are being monitored at the Cosmic Rays Laboratory, PGI, Apatity, using an integrated set based on the SCR basic components detectors. Also, besides stationary equipment, a mobile complex has been developed and made, which consists of a scintillation spectrometer, a charged component detector (CCD) based on the Geiger-Muller counters, and a neutron component detector (Е > 1 MeV) based on helium counters SNM-18. The mobile complex was put into operation in the early 2019. It operates in parallel with the basic equipment, recording SCRs. Small dimensions, effective energy consumption and ability to record data onto flash drives allows this complex to be used in SCR-monitoring in remote places, as well as on ships away at sea.

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26

Guo, Hongcheng, Peter K. Zeitler, Bruce D. Idleman, Annia K. Fayon, Paul G. Fitzgerald, and Kalin T. McDannell. "Helium diffusion systematics inferred from continuous ramped heating analysis of Transantarctic Mountains apatites showing age overdispersion." Geochimica et Cosmochimica Acta 310 (October 2021): 113–30. http://dx.doi.org/10.1016/j.gca.2021.07.015.

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27

Chen, Xiaojing, Natalia Karpukhina, Delia S. Brauer, and Robert G. Hill. "Novel Highly Degradable Chloride Containing Bioactive Glasses." Biomedical glasses 1, no. 1 (January 15, 2015). http://dx.doi.org/10.1515/bglass-2015-0010.

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AbstractAddition of CaF2 to a silicate bioactive glass favours formation of fluorapatite, which is less soluble in acidic environment than hydroxyapatite. However, excess CaF2 in the glass is problematic, owing to the formation of crystalline calcium fluoride rather than fluorapatite on immersion. In this paper we investigate chloride as an alternative to fluoride in bioactive silicate glasses and in particular their bioactivity for the first time. Meltderived bioactive glasses based on SiO2-P2O5-CaO-CaCl2 with varying CaCl2 contents were synthesised and characterised by DSC. Chemical analysis of the chloride content was performed by using an ion selective electrode. Glass density was determined using Helium Pycnometry. The glass bioactivity was investigated in Tris buffer. Ion release measurements were carried out by using ICP-OES. The chemical analysis results indicated that the majority of the chloride is retained in the Q2 type silicate glasses during synthesis. Tg and glass density reduced with increasing CaCl2 content. Apatite-like phase formation was confirmed by FITR, XRD and 31P MAS-NMR. The results of the in vitro studies demonstrated that the chloride containing bioactive glasses are highly degradable and form apatite-like phase within three hours in Tris buffer and, therefore, are certainly suitable for use in remineralising toothpastes. The dissolution rate of the glass was found to increase with CaCl2 content. Faster dissolving bioactive glasses may be attractive for more resorbable bone grafts and scaffolds.

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28

Gong, W. L., L. M. Wang, R. C. Ewing, L. F. Chen та W. Lutze. "Transmission Electron Microscopy Study of α-Decay Damage in Aeschynite and Britholite". MRS Proceedings 465 (1996). http://dx.doi.org/10.1557/proc-465-649.

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ABSTRACTThe aeschynite structure-type (Ce,Nd,La,Th,U,Ca)(Nb,Ti)2O6, and the rare-earth silicate apatite structure-type with the formula (Ce,La,Nd,Ca,Th)10(SiO4,PO4)6(O,F,OH)2 are important rare-earth and actinide host phases for high-level nuclear waste. Natural phases of these structure-types have calculated alpha-decay doses up to ∼1017 α-events/mg which have accumulated over hundreds of millions of years. Transmission electron microscopy has been used to study the microstructure of α-decay damage in aeschynite and britholite. Electron diffraction analysis of natural aeschynite revealed that minerals originally crystalline gradually lost their crystallinity with increasing alpha-decay doses. Helium bubbles were found in the aeschynite which have accumulated up to ∼2×1016 α-events/mg. These bubbles may nucleate within collision cascades during a-decay damage. Electron irradiation has an enhanced rare-gas migration and the formation of larger bubbles. High-resolution electron microscopy (HRTEM) revealed that amorphization during accumulation of a-decay damage was from alpha-recoil nuclei collision cascades, in both the aeschynite and britholite.

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29

Cuffey, Kurt M., Alka Tripathy-Lang, Matthew Fox, Greg M. Stock, and David L. Shuster. "Late Cenozoic deepening of Yosemite Valley, USA." GSA Bulletin, October 19, 2022. http://dx.doi.org/10.1130/b36497.1.

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Although Yosemite Valley, USA, catalyzed the modern environmental movement and fueled foundational debates in geomorphology, a century of investigation has failed to definitively determine when it formed. The non-depositional nature of the landscape and homogeneous bedrock have prevented direct geological assessments. Indirect assumptions about the age of downcutting have ranged from pre-Eocene to Pleistocene. Clarity on this issue would not only satisfy public interest but also provide a new constraint for contentious debates about the Cenozoic tectonic and geomorphologic history of the Sierra Nevada in California. Here we use thermochronometric analysis of radiogenic helium in apatite crystals, coupled with numerical models of crustal temperatures beneath evolving topography, to demonstrate significant late Cenozoic deepening of Tenaya Canyon, Yosemite’s northeastern branch. Approximately 40%−90% of the current relief has developed since 10 Ma and most likely since 5 Ma. This coincides with renewed regional tectonism, which is a long-hypothesized but much debated driver of Sierran canyon development. Pleistocene glaciation caused spatially variable incision and valley widening in Yosemite Valley, whereas little contemporaneous erosion occurred in the adjacent upper Tuolumne watershed. Such variations probably arise from glacial erosion’s dependence on opographic focusing of ice discharge into zones of rapid flow, and on the abundance of pre-existing fractures in the substrate. All available data, including those from our study, are consistent with a moderately high and slowly eroding mid-Cenozoic Sierra Nevada followed by significant late Cenozoic incision of some, but not all, west-side canyons. A likely driver of this event was range-crest uplift accompanied by fault-induced beheading of some major drainages, although other mechanisms such as drainage reorganization following volcanic deposition are plausible.

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