ID-TIMS Sm-Nd and Sr Isotope Ratios of Reference Material Basalt Ribeirao Preto (BRP-1)

This work presents Sm-Nd and Sr isotopic ratios of the BRP-1 (Basalt Ribeirao Preto) reference material (RM) based on repeated TIMS measurements over twelve years carried out by the LAGIR laboratory, Brazil. The BRP-1 RM was produced by the Brazilian Geological Survey from a ca. 130 Ma within-plate basalt, collected from a quarry near Ribeirao Preto city in the Parana basin. Isotope ratios were measured using a TRITON mass spectrometer. Instrumental bias and fractionation corrections were performed based on repeated measurements of the certified RMs JNdi-1 and NIST SRM 987. The measured Nd and Sr isotopic ratios of BRP-1 are: Nd-143/Nd-144 = 0.512408 +/- 0.000010 (2s), and Sr-87/Sr-86 = 0.706011 +/- 0.000017 (2s). The mass fractions of Sm and Nd are 11.0 +/- 0.2 and 51.9 +/- 0.6 mu g g(-1), respectively, showing no significant differences compared with the accepted values from the literature. No significant difference between measurements was observed, whether digesting samples in single or batch mode, using metal-jacketed PTFE bombs or PFA vials, or with or without the addition of a spike. The accuracy of these results was evaluated through the measurement of well-characterised USGS RMs, such as AGV-1, BCR-1, BHVO-1, G-2 and GSP-1.

Automated summary

This study presents Sm-Nd and Sr isotopic ratios of the BRP-1 reference material based on repeated TIMS measurements over a 12-year period. The BRP-1 material was derived from a ca. 130 Ma within-plate basalt collected in Brazil. The measured isotopic ratios for BRP-1 show no significant differences from accepted values in the literature.