Shergottite Lead Isotope Signature in Chassigny and the Nakhlites
نویسنده
چکیده
Introduction: The nakhlites/chassignites and the shergottites represent two differing suites of basaltic martian meteorites. The shergottites have ages ≤ 0.6 Ga and a large range of initial Sr/Sr and e(Nd) ratios. Conversely, the nakhlites and chassignites cluster at 1.3-1.4 Ga and have a limited range of initial Sr/Sr and e(Nd) [1]. More importantly, the shergottites have e(W) < 1, whereas the nakhlites and chassignites have e(W) ~ 3 [2]. This latter observation precludes the extraction of both meteorite groups from a single source region. However, recent Pb isotopic analyses indicate that there may have been interaction between shergottite and nakhlite/chassignite Pb reservoirs.
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