Rb-Sr and Sm-Nd isotopic systematics of the lherzolitic shergottite GRV 99027

– Rb-Sr and Sm-Nd isotopic analyses of the lherzolitic shergottite Grove Mountains (GRV) 99027 are reported. GRV 99027 yields a Rb-Sr mineral isochron age of 177 ± 5 (2σ) Ma and an initial 87Sr/86Sr ratio (ISr) of 0.710364 ± 11 (2σ). Due to larger uncertainties of the Sm-Nd isotopic data, no Sm-Nd isochron age was obtained for GRV 99027. The e143Nd value is estimated approximately +12.2, assuming an age of 177 Ma. The ISr of GRV 99027 is distinguishable from other lherzolitic shergottites, confirming our previous conclusion that it is not paired with them (Lin et al. 2005). The new data of GRV 99027 support the same age of approximately 180 Ma for most lherzolitic shergottites, and fill the small gap of ISr between Allan Hills A77005 and Lewis Cliff 88516 (Borg et al. 2002). All available data are consistent with a single igneous source for the intermediate subgroup of lherzolitic shergottites.