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J. Benbakkar, This 711 project has received funding from the European Research Council (ERC) under the European Union's 712 Horizon 2020 research and innovation programme (Grant Agreement No 682778 -ISOREE) and from 713 the Clervolc Labex

, SiO2 and (b) MgO concentrations in the samples analysed in this study. The 723 colours are for the two series (red for high-K and blue for low-K) observed in the Fangataufa samples, Figure 1: K2O vs (a), vol.724

, Figure 2: MgO vs La/Yb ratios for the samples analysed in this study. Colours defined in Fig, vol.1

, Figure 3: ?NdCHUR versus Sr isotopic composition for Ocean Island basalts. The blue and red circles are 766 the data from this study (colours defined in Figure 1). The black squares are Fangataufa samples from 767

. Bardintzeff, The grey circles are OIB samples from the literature, p.768, 1994.

, Cr versus Nd isotopic compositions for the Fangataufa basalts. The colour coding is defined, Figure, vol.5

, Figure 8: ? 53 Cr versus the amount of Cr left (F) in the melt during fractional crystallisation for the 857

F. Bonnand, F was 858 calculated using the equation: F = Crsample / Crmax, where Crmax is the highest, p.859, 2016.

L. Fangataufa and . Basalts, The grey horizontal bars are the current estimates of the BSE (dark grey, p.860

. Sossi, The dotted line is a Rayleigh fractionation model 861 for lunar basalts. The blue and red shaded areas are the fractional models for the low-K and high-K 862 suites, respectively. The isotopic fractionation (? 53 Cr) used for Fangataufa basalts, 2008.

, For the lunar basalts, the fractionation factor is 864 -0.07 ? (see text for details). Error bars are the external reproducibility reported in each study

S. Figure, Chondrite normalised REE patterns for Fangataufa basalts. The OIB data is from Sun and 963

;. Mcdonough and . Gale, The chondrite values 964 used for normalisation is from, The colour coding is defined in Figure S1, 1989.