Experimental partitioning of Be, Cs, and other trace elements between cordierite and felsic melt, and the chemical signature of S-type granite

Evensen, Joseph M.; London, David

doi:10.1007/s00410-002-0426-x

Cited by 44 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The high incompatibility of Cs in nearly all of the principal rock-forming minerals (except cordierite: Evensen and London, 2003) means that its concentration in partial melts is unbuffered by subsequent crystallization. It is, therefore, a useful diagnostic of the parental source of pegmatites, which are the products of protracted fractional crystallization of larger igneous bodies (e.g., Černý et al 1985;Černý 1991;London, 2008London, , 2019.…”

Section: Discussionmentioning

confidence: 99%

A Rayleigh model of cesium fractionation in granite-pegmatite systems

London

2022

American Mineralogist

Self Cite

View full text Add to dashboard Cite

The K/Cs ratios of K-feldspars from granitic pegmatites are compared to models derived from the Rayleigh equation. The K/Cs and K/Rb ratios of K-feldspars and micas exhibit decreasing values when plotted against their Cs or Rb contents across cogenetic suites of granites and pegmatites, and from margin to core of individual bodies. The trends in elemental ratios conform to Rayleigh fractionation for the crystallization of feldspars and micas from a silicate melt. Within two individual pegmatite bodies, the K/Cs ratio of K-feldspar initially falls more rapidly than the Rayleigh model predicts. That might reflect a local increase in the concentration of Cs relative to K due to the pile-up of incompatible elements in a boundary layer of melt adjacent to the crystal growth front. The addition of an aqueous solution to the Rayleigh model (i.e., the simultaneous crystallization of K-feldspars from melt and from aqueous solution) predicts high and increasing K/Cs ratios of K-feldspars that are not observed in natural rock suites, except when K-feldspars crystallize in miarolitic cavities or when primary K-feldspar recrystallizes to microcline perthite in an open hydrothermal system. In those cases, the Cs content of K-feldspars falls to nil because of the high solubility of Cs in aqueous solution and low compatibility of Cs in K-feldspar. Otherwise, the observed patterns of K/Rb or K/Cs in K-This is the peer-reviewed, final accepted version for American Mineralogist, published by the Mineralogical Society of America.The published version is subject to change. Cite as Authors (Year) Title. American Mineralogist, in press.

show abstract

Section: Discussionmentioning

confidence: 99%

A Rayleigh model of cesium fractionation in granite-pegmatite systems

London

2022

American Mineralogist

Self Cite

View full text Add to dashboard Cite

show abstract

“…Fractionation of Cs into magmatic cordierite (Dg dlmelt = 31.5 ± 1.6;Bea et al 1994) has in fact been invoked by several authors (e.g. London 1995;Cerny et al 1997;Evensen and London 2003;Bertoldi et al 2004). …”

Section: Na-and Li-rich Cordieritementioning

confidence: 96%

Andalusite and Na- and Li-rich cordierite in the La Costa pluton, Sierras Pampeanas, Argentina: textural and chemical evidence for a magmatic origin

Alasino

Dahlquist

Galindo

et al. 2009

Int J Earth Sci (Geol Rundsch)

View full text Add to dashboard Cite

AbstraetThe La Costa pluton in the Sierra de Velasco (NW Argentina) consists of S-type granitoids that can be grouped into three igneous facies: the alkali-rich Santa Cruz facies (SCF, Si0 2 ",67 wt%) mstinguished by the presence of andalusite and Na-and Li-rich cormerite (Na20 = 1.55-1.77 wt% and LhO = 0.14---0.66 wt%), the Anillaco facies (Si0 2 '" 74 wt%) with a significant proportion of Mn-rich garnet, and the Anjullón facies (Si0 2 '" 7 5 wt%) with abundant albitic plagioc1ase. The petrography, mineral chemistry and whole-rock geochemistry of the SCF are compatible with magmatic crystallization of Na-and Li-rich cormerite, andalusite and muscovite from the peraluminous magma under moderate P-T conditions ('" 1.9 kbar and ca. 735°C). The high Li content of cormerite in the SCF is unusual for granitic rocks of intermemate composition.

show abstract

“…The age data indicate that there is a distinct gap (20~11 Ma) between the crystallization ages of the wall zone and the intermediate zone of No.1 pegmatite. The partition coefficient of beryllium in most rock-forming minerals is less than 1 (quartz C B mineral(min) /C Be melt = 0.24, K-feldspar C Be min /C Be melt = 0.3, plagioclase: An1-5 C Be min /C Be melt = 0.10 and An10-15: C Be min /C Be melt = 0.6) [70]. The intermediate zone formed after a long time of residual pegmatite melt evolution, beryllium is further enriched in the residual melt to form large and euhedral beryl crystals in the intermediate zone.…”

Section: Enrichment Mechanism Of Berylliummentioning

confidence: 99%

Beryl Mineralogy and Fluid Inclusion Constraints on the Be Enrichment in the Dakalasu No.1 Pegmatite, Altai, NW China

et al. 2022

View full text Add to dashboard Cite

The Dakalasu No.1 pegmatitic rare-element deposit is a representative of Be-Nb-Ta pegmatites in Altai, Xinjiang, China. Beryl is the most important beryllium-carrying mineral in Dakalasu No.1 pegmatite. To constrain the concentration mechanism of Be, we conducted a study of the textural relationships and chemical compositions (major and trace elements) of beryl, along with microthermometry and Raman spectroscopy on beryl-hosted fluid inclusions. Two generations of beryl were recognized. The early beryl I was formed in the magmatic stage, whereas the late beryl IIa and IIb were formed in the magmatic-hydrothermal stage. Lithium and Cs contents increased from beryl I, beryl IIa, to beryl IIb, whereas Mg and Rb contents decreased. Scandium, V, and Ga contents of beryl IIa are similar to beryl IIb, but different in beryl I. Titanium is enriched in beryl IIa. The high FeO contents and Na/Cs ratios of beryl (I, IIa, and IIb) reveal the low degree of differentiation evolution of the Dakalasu No.1 pegmatite. Two types of melt inclusions and four types of fluid inclusions were identified in beryl IIa, IIb, and associated quartz. The microthermometry results indicated that beryl II is formed at 500 °C–700 °C, and 200 MPa–300 MPa. The Dakalasu No.1 pegmatite melt is enriched in volatiles, such as B, F, and CO2, evidenced by a large amount of tourmaline in the wall zone, the occurrence of a variety of tiny cryolite (Na3AlF6) inclusions, and CO2-rich fluid inclusions in beryl IIa. The enrichment mechanism of Be may be related to the crystallization of beryl at highly undercooled states of melt, and melt–melt–fluid immiscibility during the evolution and differentiation of the melt.

show abstract

Experimental partitioning of Be, Cs, and other trace elements between cordierite and felsic melt, and the chemical signature of S-type granite

Cited by 44 publications

References 0 publications

A Rayleigh model of cesium fractionation in granite-pegmatite systems

A Rayleigh model of cesium fractionation in granite-pegmatite systems

Andalusite and Na- and Li-rich cordierite in the La Costa pluton, Sierras Pampeanas, Argentina: textural and chemical evidence for a magmatic origin

Beryl Mineralogy and Fluid Inclusion Constraints on the Be Enrichment in the Dakalasu No.1 Pegmatite, Altai, NW China

Contact Info

Product

Resources

About