Ejection ages from krypton-81-krypton-83 dating and pre-atmospheric sizes of martian meteorites
نویسندگان
چکیده
منابع مشابه
The pre-atmospheric size of Martian meteorites
φn = P'(Krn)/σ79, (3) where P'(Krn) = 2.33 Â P(Krn) and has the dimension neutrons cms. The resonance integral σ79 is 110 Â cm [3]. Fig. 1 demonstrates the resulting neutron fluxes. They are shown in relation to the fluxes of > 5 MeV neutrons that were calculated based on cosmogenic Ne [8]. Two scenarios are possible how the meteoritic material might have experienced the observed neutron fluxes...
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Long-lived radioactive krypton isotopes, (81)Kr (t1/2 = 229,000 year) and (85)Kr (t1/2 = 10.76 year), are ideal tracers. (81)Kr is cosmogenic and can be used for dating groundwater beyond the (14)C age. (85)Kr is a fission product and can be applied in atmospheric studies, nuclear safety inspections, and dating young groundwater. It has long been a challenge to analyze radio-krypton in small sa...
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The chemical element krypton, whose principal source is the atmosphere, had a long-lived radioactive content, in the mid-1940s, of less than 5 dpm per liter of krypton. In the late 1940s, this content had risen to values in the range of 100 dpm per liter. It is now some hundred times higher than the late 1940 values. This radioactivity is the result of the dissolving of nuclear fuel for militar...
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I have used the SALE2D hydrocode to study spall in impacts into layered terrains. Application of my results to the problem of martiaji meteorite provenance resolves two outstanding paradoxes. First, the minimum size crater previously thought to be required to eject martian meteorites is so large (12 km) that it is highly unlikely such an event occurred on shergottite age terrain in the Icist fe...
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ژورنال
عنوان ژورنال: Meteoritics & Planetary Science
سال: 2002
ISSN: 1086-9379,1945-5100
DOI: 10.1111/j.1945-5100.2002.tb01033.x