Zircon solubility and zirconium complexation in H2O+Na2O+SiO2±Al2O3 fluids at high pressure and temperature

Wilke, Max; Schmidt, Christian; Dubrail, Julien; Appel, Karen; Borchert, Manuela; Kvashnina, Kristina O.; Manning, Craig E.

doi:10.1016/j.epsl.2012.06.054

Cited by 120 publications

(50 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Second, almost all primitive arc basalts have Ti and Zr concentrations exceeding those that could be derived by melting of a mantle source only (Figure ). Consequently, small amounts of TiO 2 and Zr (and e.g., Dy, supporting information S1) are mobilized from the slab in all subduction zones, in line with experiments that have shown solubilities of Zr and Ti in fluids to reach hundreds of ppm [ Wilke et al ., ; Antignano and Manning , ]. Third, in many of the continental calc‐alkaline basalts, Ti and Zr concentrations reach values 2–4 times those that could be derived from mantle melting (Figure ) supplying strong evidence for addition of a Ti‐ and Zr‐rich slab melt component in continental settings.…”

Section: Discussion Of Arc Melt Components and Formation Conditionsmentioning

confidence: 96%

The global systematics of primitive arc melts

Schmidt

Jagoutz²

2017

Geochem Geophys Geosyst

190

122

View full text Add to dashboard Cite

We extracted all volcanic arc rock analyses calculated to be in equilibrium with mantle olivine from the global georoc database. This results in 938 primitive melt compositions from 30 arcs. Based on geochemical criteria six principal types of primitive arc melts can be distinguished: calc‐alkaline basalts and andesites, tholeiitic basalts, highly depleted tholeiitic andesites, shoshonites and low‐Si basalts. Their major element systematics indicates that last mantle equilibration occurred mostly at 1.0–2.5 GPa, 1220–1350°C for tholeiitic and calc‐alkaline basalts, at 0.5–1.2 GPa and ∼1200°C for depleted tholeiitic andesites, and at 0.7–1.2 GPa, 1050–1150°C for calc‐alkaline andesites. Quantitative treatment of major and trace elements suggests that the different melt types can be explained by a combination of variable mantle wedge preconditioning (degree of depletion prior to slab component addition, metasomatism in the lithosphere), variation in the amount and nature of the slab component added, and ‐ for primitive calc‐alkaline andesites ‐ reactive fractionation in the lithospheric top of the mantle wedge. The different slab components are best characterized by high Na2O, TiO2, Zr and Th for slab melts; high K2O/Na2O and more pronounced Nb, Sr, and Pb anomalies for fluids; and high K2O at high K2O/Na2O for supercritical liquids. A slab component that is dominantly a slab melt is common in continental but rare in intra‐oceanic arcs, consistent with comparatively cooler slabs in intra‐oceanic subduction zones. A majority of the arcs has more than one melt type, testifying for heterogeneity in the mantle wedge and added slab component.

show abstract

Section: Discussion Of Arc Melt Components and Formation Conditionsmentioning

confidence: 96%

The global systematics of primitive arc melts

Schmidt

Jagoutz²

2017

Geochem Geophys Geosyst

190

122

View full text Add to dashboard Cite

show abstract

“…Because the solubility of essential mineral structural components such as Ce in monazite increases exponentially with increasing temperature, only small amounts of anatectic melts are required to completely exhaust the accessory phase at temperatures >1,000°C (Stepanov et al 2012). On the other hand, the dissolution of zircon into aqueous fluids can be significantly enhanced by the contemporaneous dissolution of Na-Al silicate components (Wilke et al 2012). Therefore, the composition of subductionzone fluids is dictated by the property of chemical reactions with passing rocks, which exerts substantial influence on the mobility of HFSE during subduction-zone metamorphism.…”

Section: Composition Of Continental Subduction-zone Fluids Experimentmentioning

confidence: 99%

Geochemistry of continental subduction-zone fluids

2014

View full text Add to dashboard Cite

The composition of continental subduction-zone fluids varies dramatically from dilute aqueous solutions at subsolidus conditions to hydrous silicate melts at supersolidus conditions, with variable concentrations of fluid-mobile incompatible trace elements. At ultrahigh-pressure (UHP) metamorphic conditions, supercritical fluids may occur with variable compositions. The water component of these fluids primarily derives from structural hydroxyl and molecular water in hydrous and nominally anhydrous minerals at UHP conditions. While the breakdown of hydrous minerals is the predominant water source for fluid activity in the subduction factory, water released from nominally anhydrous minerals provides an additional water source. These different sources of water may accumulate to induce partial melting of UHP metamorphic rocks on and above their wet solidii. Silica is the dominant solute in the deep fluids, followed by aluminum and alkalis. Trace element abundances are low in metamorphic fluids at subsolidus conditions, but become significantly elevated in anatectic melts at supersolidus conditions. The compositions of dissolved and residual minerals are a function of pressure-temperature and whole-rock composition, which exert a strong control on the trace element signature of liberated fluids. The trace element patterns of migmatic leucosomes in UHP rocks and multiphase solid inclusions in UHP minerals exhibit strong enrichment of large ion lithophile elements (LILE) and moderate enrichment of light rare earth elements (LREE) but depletion of high field strength elements (HFSE) and heavy rare earth elements (HREE), demonstrating their crystallization from anatectic melts of crustal protoliths. Interaction of the anatectic melts with the mantle wedge peridotite leads to modal metasomatism with the generation of new mineral phases as well as cryptic metasomatism that is only manifested by the enrichment of fluid-mobile incompatible trace elements in orogenic peridotites. Partial melting of the metasomatic mantle domains gives rise to a variety of mafic igneous rocks in collisional orogens and their adjacent active continental margins. The study of such metasomatic processes and products is of great importance to understanding of the mass transfer at the slab-mantle interface in subduction channels. Therefore, the property and behavior of subduction-zone fluids are a key for understanding of the crust-mantle interaction at convergent plate margins.

show abstract

“…In the MgO-SiO 2 -H 2 O system, for example, the solubility in the aqueous fluid decreases with increasing Mg/Si abundance ratio (Zhang and Frantz 2000). Addition of aluminosilicate components to SiO 2 also enhances the solubility in fluid (Wilke et al 2012). However, quantitative characterization of how individual components affect silicate solubility and solution mechanisms of other components in aqueous fluids is not well developed.…”

Section: Introductionmentioning

confidence: 99%

Silicate solution, cation properties, and mass transfer by aqueous fluid in the Earth’s interior

Mysen

2018

Prog Earth Planet Sci

View full text Add to dashboard Cite

Aqueous fluids in the Earth's interior are multicomponent systems with silicate solubility and solution mechanisms strongly dependent on other dissolved components. Here, solution mechanisms that describe the interaction between dissolved silicate and other solutes were determined experimentally to 825°C and above 1 GPa with in situ vibrational spectroscopy of aqueous fluid while these were at high temperature and pressure. The silicate content in Na-bearing, silicate-saturated aqueous fluid exceeds that in pure SiO 2 at high temperature and pressure. Silicate species were of Q 0 (isolated SiO 4 tetrahedra) and Q 1 (dimers, Si 2 O 7 ) type. The temperature dependence of its equilibrium constant, K = X Q1 /(X Qo ) 2 , yields enthalpies of 22 ± 12 and 51 ± 17 kJ/mol for the SiO 2 -H 2 O and Na-bearing fluids. In contrast, in Ca-bearing fluids, the solubility is more than an order of magnitude lower, and only Q 0 species are present. The present data together with other published experimental information lead to the conclusion that the silicate solubility in aqueous fluids in equilibrium with mafic rocks such as amphibolite and peridotite is an order of magnitude lower than the solubility in fluids in equilibrium with felsic rocks such as andesite and rhyolite compositions (felsic gneiss) under similar temperature and pressure conditions. The silicate speciation also is more polymerized in the felsic systems. This difference is also why second critical end-points in the Earth are at lower temperature and pressure in felsic compared with mafic systems. Alkali-rich fluids formed by dehydration of felsic rocks also show enhanced high field strength element (HFSE) solubility because alkalis in such solution form oxy complexes with the HFSE cations. Fluids formed by dehydration of felsic rocks in the Earth's interior are, therefore, more efficient transport agents of silicate materials than fluids formed by dehydration of mafic and ultramafic rocks, whether for major, minor, or trace elements.

show abstract

Zircon solubility and zirconium complexation in H2O+Na2O+SiO2±Al2O3 fluids at high pressure and temperature

Cited by 120 publications

References 60 publications

The global systematics of primitive arc melts

The global systematics of primitive arc melts

Geochemistry of continental subduction-zone fluids

Silicate solution, cation properties, and mass transfer by aqueous fluid in the Earth’s interior

Contact Info

Product

Resources

About