Oxygen isotopic fractionation in the system quartz-albite-anorthite-water

Matsuhisa, Yukihiro; Goldsmith, Julian R.; Clayton, Robert N.

doi:10.1016/0016-7037(79)90099-1

Cited by 741 publications

(384 citation statements)

References 25 publications

Supporting

Mentioning

364

Contrasting

Unclassified

Order By: Relevance

“…Matsuhisa, 1979;Matthews et al, 1983a,b). More recently, three studies applied this method to the Fe isotope systematics: between oxide and silicate phases at high temperature (Shahar et al, 2008), between chloro-complexes in aqueous solutions (Hill and Schauble, 2008), and between Fe(II) aq and goethite (Beard et al, 2010).…”

Section: The Three Isotope Methodsmentioning

confidence: 99%

Fe isotope exchange between Fe(II)aq and nanoparticulate mackinawite (FeSm) during nanoparticle growth

Guilbaud

Butler

Ellam

et al. 2010

Earth and Planetary Science Letters

View full text Add to dashboard Cite

show abstract

Section: The Three Isotope Methodsmentioning

confidence: 99%

Fe isotope exchange between Fe(II)aq and nanoparticulate mackinawite (FeSm) during nanoparticle growth

Guilbaud

Butler

Ellam

et al. 2010

Earth and Planetary Science Letters

View full text Add to dashboard Cite

show abstract

“…Quartz and muscovite from VM show δ 18 O values of 10.9 and 9.3 ‰, respectively. Assuming equilibrium, this quartz-muscovite pair yields a formation temperature of 673°C (Chacko et al 1996), whereas the fluid in equilibrium with the minerals has a δ 18 O value of 10.5 ‰ (Matsuhisa et al 1979). This value most likely reflects magmatic origin (Sheppard 1986).…”

Section: Oxygen Isotopesmentioning

confidence: 99%

The Paleoproterozoic metaconglomerate-hosted Castelo de Sonhos gold deposit, Tapajós Gold Province, Amazonian Craton: a modified paleoplacer origin

Queiroz¹,

Klein

2018

JGSB

View full text Add to dashboard Cite

The Castelo de Sonhos gold deposit (~1.5 Moz Au) is located in the southeastern Tapajós Gold Province and is hosted in variably deformed metaconglomerates and metasandstones of the Castelo dos Sonhos Formation, which was deposited between 2011 and 2050 Ma and considered to be a relic of a major foreland system. Gold is found mainly in the matrix of metaconglomerates and subordinately in fractures of metasandstones. The host rocks are strongly silicified, which was demonstrated to be the result of silica overgrowth during diagenesis, without relationship to hydrothermal alteration. The rocks are also impregnated with secondary iron oxides, which are interpreted to be consequence of weathering of the metasedimentary sequence and total or partial dissolution of iron-bearing minerals and re-precipitation of iron during circulation of oxidized (meteoric and/or magmatic) fluids. The morphology of matrix gold particles indicates that they are not pristine, but only slightly modified and reshaped, which suggests detrital provenance and relatively proximal distance of transport from the original sources. The chemical composition of the particles, with Au grading 94-97%, very high Au/ Ag and lack of other significant metals, suggest single source, or sourcing from a single class (orogenic?) of gold deposits. The gold particles from fractures are platy and show even higher Au/Ag ratios, given by very low Ag contents (<<1%), which are interpreted as epigenetic remobilization of the matrix gold. Oxygen isotope compositions of hydrothermal quartz-sulfide-muscovite veins cutting across the host metasedimentary sequence indicate magmatic origin for the fluids, which might have been produced by granites that intruded the metasedimentary rocks and helped gold remobilization to fractures. As a consequence, Castelo de Sonhos is interpreted as a modified paleoplacer gold deposit.

show abstract

“…The vertical lines indicate the range for magmatic fluids derived from normal granites. Figures have been designed using the appropriate mineral-H20 fractionation factors for quartz (Clayton etal., 1972), K-feldspar (O'Neil and Taylor, 1967) and muscovite (Bottinga and Javoy, 1973 Note that the higher values for each temperature were calculated using the albite-H20 equilibria of Matsuhisa et al (1979) while the lower values were obtained using the equation of Bottinga and Javoy (1973).…”

Section: Nature Of Fluids In the Late-stage Evolution Of The Batholithmentioning

confidence: 99%

The role of fluids in the late-stage evolution of the South Mountain Batholith, Nova Scotia: further geochemical and oxygen isotopic studies

Kontak

Kerrich

Strong

1991

atgeol

View full text Add to dashboard Cite

In order to evaluate the late-stage physical and chemical evolution of the Upper Devonian, peraluminous South Mountain Batholith, mineral chemistry (muscovite, feldspars), oxygen isotopes (whole rock, mineral separates) and Al/Si ordering of Kfeldspar have been investigated. Muscovite, K-feldspar and albite define coherent chemical trends with respect to compatible (B a, Sr, Eu) and incompatible (Li, Cs, Rb) elements such that crystal fractionation processes are reflected. However, the influence of a fluid phase is seen in terms of Eu/Eu* of greisen muscovite and the light REE profiles (chondritic) of chemically evolved K-feldspar. The dominance of monoclinic K-feldspar, even in pegmatitic environments, indicates that either single or multiple processes impeded Al/Si ordering (e.g., cooling rate, fluid and/or rock composition). However, locally the development of triclinic K-feldspar dominates where intense fluid-rock interaction occurred (e.g., greisens), thus reflecting alteration at temperatures <450"C. 5lsO values of minerals from pegmatites reflect disequilibrium conditions related to variable degrees of fluid-rock interaction after crystallization. Calculated 81 * 0^ (mostly 5-10 %>) indicates a dominantly magmatic fluid reservoir; bo th 1 ®Q-enriched (to +18 %») and -depleted (to <+4 %<>) fluids infiltrated the system, indicating that local fluid mixing occurred.Dans le but d'6valuer Involution physique et chimique dans ses demiers stades du batholite peralumineux devonien superieur de South Mountain, on a 6tudie la chimie des min£raux (muscovite, feldspaths), les isotopes de l'oxygene (sur roche totale et sur fractions monominerales) et l'ordonnance Al/Si au sein des feldspaths potassiques. La muscovite, le feldspath potassique et l'albite d&erminent des tendances chimiques coh&entes vis-a-vis des elements compatibles (Ba, Sr, Eu) et incompatibles (Li, Cs, Rb), de fa5on telle qu'elles refletent des processus de cristallisation fractionnee. Cependant, l 'influenee d 'une phase fluide s 'exprime en termes du rapport Eu/Eu* des muscovites dans les greisens et des profils (chondritiques) des T.R. legeres de feldspaths potassiques ayant subi une Evolution chimique. La dominance du feldspath potassique monoclinique, meme dans les environnements pegmatitiques, indique qu'un ou plusieurs processus firent entrave a l'ordonnance Al/Si (e.g., taux de refroidissement, composition du fluide et/ou de la roche). Cependant, d 'une faijon locale, le developpement de feldspath potassique triclinique domine la oil l 'int^raction entre le fluide et la roche fut intense (e.g., dans les greisens), refletant ainsi une alteration a des temperatures atteignant 450°C. Le dosage 81 ®0 des mineraux preleves dans les pegmatites reflete des conditions de desequilibre reliees a divers degres d 'interaction entre le fluide et la roche apres leur cristallisation. La valeur calcuiee 81 * 0^^ (pour la plupart 5-10 %<>) indique un reservoir de fluide a dominance magmatique; le systeme fut infiltre par des fluides aussi bien enrichis (jusqu...

show abstract

Oxygen isotopic fractionation in the system quartz-albite-anorthite-water

Cited by 741 publications

References 25 publications

Fe isotope exchange between Fe(II)aq and nanoparticulate mackinawite (FeSm) during nanoparticle growth

Fe isotope exchange between Fe(II)aq and nanoparticulate mackinawite (FeSm) during nanoparticle growth

The Paleoproterozoic metaconglomerate-hosted Castelo de Sonhos gold deposit, Tapajós Gold Province, Amazonian Craton: a modified paleoplacer origin

The role of fluids in the late-stage evolution of the South Mountain Batholith, Nova Scotia: further geochemical and oxygen isotopic studies

Contact Info

Product

Resources

About