The influence of pressure, mineral composition and water on trace element partitioning between clinopyroxene, amphibole and basanitic melts

Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

“…The offset between REE concentrations predicted using the two experiments (RN8 Inner and RN13V2) highlights the extent to which amphibole partition coefficients vary with melt fractionation. Melts predicted using the partition coefficients from Sisson (1994) and Adam and Green (2003) have the same relative trends as those from Nandedkar et al (2016) and suggest early amphibole grains crystallised from a primitive melt with a flat REE profile. The late, interstitial amphibole was crystallised from a melt enriched in LREE, similar to both the erupted lava whole-rock compositions and the melt in equilibrium with amphiboles in non-cumulate gabbros (Fig.…”

“…Clinopyroxene partition coefficients from Adam and Green (2003) and Wood and Blundy (1997) reveal the melts in equilibrium with clinopyroxene associated with both amphibole types have similarly contrasting REE compositions. The shape of the REE profile for melt in equilibrium with clinopyroxene associated with interstitial amphibole is very similar to the melt in equilibrium with interstitial amphibole.…”

“…This observation implies that an addition of trace elements, in particular LREE into the system must have occurred after clinopyroxene crystallisation and before amphibole crystallisation. To assess the contribution of elements (Li, Al, Ti, Ga, Rb, Sr, Y, Zr, Hf, Nb, Ta, Ba, La, Ce, Sm, Ho, Yb, Lu, Th, U) from clinopyroxene to produce reaction replacement amphiboles, the melt produced from the breakdown of clinopyroxene was modelled using partition coefficients (run at 1025 °C, 0.5 GPa) from Adam and Green (2003) (Fig. 13).…”

“…13). The chemistry of amphibole which then crystallised from the clinopyroxene melt was modelled using experimental amphibole partition coefficients (run at 1000 °C, 0.5 GPa) from Adam and Green (2003). If the modelled amphibole element concentrations were lower than natural interstitial amphibole, then an additional source of elements is needed (Fig.…”

Petrogênese da suíte alcalina da Ilha Monte de Trigo, SP

“…Centros ígneos rnesozóicos e cenozóicos representados principalmente por rochas alcalinas, compilados de Almeida (1983Almeida ( , 1986, Ahneida ¿t al (2000), CorninChiaramonti et al (1997), Morbidelli et al (1995), Thompson et al (1998) Best (1982), Hall (1996) Leake (1997) feldspar palhs" de Brown (1993, Fig. (Le Maitre,2002) (Alves, 1996); 2, ltaítna (Valença, 1980); 3, Morro Redondo (Brotzu er ul., 1989); 4, Soalinho (Vâlença, I 980); 5, Ilha de Vitória (Motoki, 1986); 6, tlha de São Sebasrião (Bellieni el al., 1990);7, Tanguá -Rio Bonito -Morro de São João (Valcnça, I980); 8. Itatiaia (Brotzu et dl.,1997);9, PassaQuatro(Brotzuetal.,1992 (Brögger, 1890;Kapustin & Bykova, 1965;Aarden & cittins, 1974' Egglefon el at., 1979 Mellin i, 1981Raade & Mladeck, 1983; (Garda, 1995); (4) de Bellieni et al (1990), Garda (1995), Alves (1996), Thompson et al (1998) (1985,1990), Garda et al (1995), Holfinann (1997) Ghiorso & Sack (1995) e Asimow & (1992,1994), Foley et al (1996), Adam & Green (2003), Zanetti et al (2004) Vitória (Motoki, 1986), Ilha dos Búzios (Alves, 1996), São Sebastião (Bellieni et al, 1990i Thornpson ør a/., 1998), as ilhas oceânicas de Tlindade …”