Depth variation of cosmogenic noble gases in the ∼120-kg Keyes chondrite
作者： R. J. Wright , L. A. Simms , M. A. Reynolds , D. D. Bogard
关键词: Noble gas 、 Isotopes of neon 、 Chondrite 、 Nuclear physics 、 Meteorite 、 Mineralogy 、 Materials science 、 Cosmogenic nuclide 、 Cosmic ray spallation 、 Isotopes of argon 、 Nuclide 、 Earth-Surface Processes 、 Ecology (disciplines) 、 Earth and Planetary Sciences (miscellaneous) 、 Space and Planetary Science 、 Palaeontology 、 Forestry 、 Aquatic science 、 Atmospheric Science 、 Soil science 、 Geochemistry and Petrology 、 Geophysics 、 Oceanography 、 Water Science and Technology
摘要: Cosmic ray spallation produced 3He, 21Ne, 22Ne, and 38Ar have been measured as a function of depth in three mutually perpendicular cores (56, 51, 21 cm) taken from the ∼120-kg L chondrite found near Keyes, Oklahoma. The data obtained represent first experimental determination variation production rates these cosmogenic nuclides single stone meteorite. Fifteen samples across 56-cm core showed maximum concentration changes 14% 28% 19% 3He/21Ne, 5% 22Ne/21Ne. 51-cm somewhat smaller changes. All are characterized by increasing 3He 21Ne concentrations decreasing 3He/21Ne 22Ne/21Ne ratios with depth. A relatively broad occurs at >20 cm. ranges observed Keyes (5.7–4.8 1.14–1.08, respectively) typical irradiation hardness experienced many ordinary chondrites imply shielding 5–35 These not sensitive for but offer possible means making relative corrections to calculated noble gas exposure ages.
harvard.edu
osti.gov
agu.org参考文章(28)
F. Begemann, H. Wänke, 39 K(n,p)-Produced 39 Ar in Chondrites: New Data and Their Interpretation in Terms of Size, Exposure Age and Orbital Elements ASSL. ,vol. 12, pp. 363- 371 ,(1969) , 10.1007/978-94-010-3411-1_30
T Kirsten, D Krankowsky, J Zähringer, Edelgas- und kalium-bestimmungen an einer gröβeren zahl von steinmeteoriten Geochimica et Cosmochimica Acta. ,vol. 27, pp. 13- 42 ,(1963) , 10.1016/0016-7037(63)90070-X
D. Heymann, E. Mazor, RADIATION AGES AND GAS-RETENTION AGES OF CARBONACEOUS CHONDRITES AND OF UNEQUILIBRATED ORDINARY CHONDRITES. pp 239-57 of Radioactive Dating and Methods of Low-Level Counting. Vienna, International Atomic Energy Agency, 1967.. ,(1967) , 10.2172/4511538
T. W. Armstrong, R. G. Alsmiller, Calculation of cosmogenic radionuclides in the moon and comparison with Apollo measurements LPSC. ,vol. 2, pp. 1729- ,(1971)
K. Marti, J. P. Shedlovsky, R. M. Lindstrom, J. R. Arnold, N. G. Bhandari, Cosmic-Ray Produced Radionuclides and Rare Gases Near the Surface of Saint-Séverin Meteorite Meteorite Research. ,vol. 12, pp. 246- 266 ,(1969) , 10.1007/978-94-010-3411-1_22
K. Marti, J. Geiss, P. Eberhardt, O. Eugster, RARE GAS MEASUREMENTS IN 30 STONE METEORITES Zeitschrift Fur Naturforschung Section A-a Journal of Physical Sciences. ,vol. 21, pp. 414- ,(1966)
D.D Bogard, P.J Cressy, Spallation production of 3He, 21Ne, and 38Ar from target elements in the Bruderheim chondrite Geochimica et Cosmochimica Acta. ,vol. 37, pp. 527- 546 ,(1973) , 10.1016/0016-7037(73)90216-0
W.R. Van Schmus, J.A. Wood, A chemical-petrologic classification for the chondritic meteorites. Geochimica et Cosmochimica Acta. ,vol. 31, pp. 747- 765 ,(1967) , 10.1016/S0016-7037(67)80030-9
G.F. Herzog, Edward Anders, Absolute scale for radiation ages of stony meteorites Geochimica et Cosmochimica Acta. ,vol. 35, pp. 605- 611 ,(1971) , 10.1016/0016-7037(71)90090-1
E. L. FIREMAN, Distribution of Helium-3 in the Carbo Meteorite Nature. ,vol. 181, pp. 1725- 1725 ,(1958) , 10.1038/1811725A0