New calibration data for the Fe–Ti oxide thermo-oxybarometers from experiments in the Fe–Ti–O system at 1 bar, 1,000–1,300°C and a large range of oxygen fugacities

Lattard, Dominique; Sauerzapf, Ursula; Käsemann, Martin

doi:10.1007/s00410-005-0679-2

Cited by 56 publications

(57 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Consequently, the larger stability field of ilmenite alone under reduced conditions is a consequence of magnetite destabilization, and thus iron-enrichment in the melt. On the other hand, even in oxidizing conditions, melts with a high TiO 2 content might reach ilmenite saturation before magnetite, and in some cases may only crystallize hemo-ilmenite without magnetite (Lattard et al, 2005). This situation is observed in the Grader layered intrusion (Charlier et al, 2008), where the high hematite content in ilmenite is an indicator of the high oxygen fugacity in the melt (ca.…”

Section: Fo 2 and Parental Magma Compositionmentioning

confidence: 99%

“…It has been shown that the magnetite content of magnetite-ulvöspinel series and the hematite content of ilmenite-hematite series both increase with increasingly oxidizing conditions (e.g. Buddington and Lindsley, 1964;Lattard et al, 2005;Sauerzapf et al, 2008). At given fO 2 conditions, the magnetite content of magnetite decreases with increasing temperature.…”

Section: Major Elementsmentioning

confidence: 99%

“…The ilmenite composition is less sensitive to temperature but its behavior is more complex due to the transition between the ordered R3 structure and the disordered R3C structure. At oxygen fugacity conditions below QFM + 2 (QFM = the quartz-fayalite-magnetite fO 2 buffer), the hematite-content of ilmenite increases with increasing temperature (Lattard et al, 2005). Conversely, at more oxidizing conditions, the hematite content of ilmenite decreases with increasing temperature.…”

Section: Major Elementsmentioning

confidence: 99%

See 2 more Smart Citations

Fe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks

Charlier

Namur

Bolle

et al. 2015

Earth-Science Reviews

View full text Add to dashboard Cite

a b s t r a c t a r t i c l e i n f oMagmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the anorthositemangerite-charnockite-(rapakivi-)granite suites that are restricted to the Proterozoic. Understanding the geochemistry and emplacement mechanisms of ilmenite, magnetite and apatite ore deposits is crucial for exploration, efficient mining operations and ore processing. This review discusses the controlling factors on the grade of an ore, its mineralogy, and its major and trace element distribution. We present petrogenetic models of currently mined deposits (Lac Tio, Tellnes, Damiao) and discuss the characteristics of minor ore bodies from anorthosite provinces worldwide (Grenville, North China Craton, East European Craton, Rogaland, Laramie). Models of formation of anorthosite and related rocks are presented, as well as the nature of the possible parental magmas of the suite. A mineralogical classification of Fe-Ti ores is proposed: (1) Gabbro-noritic ilmenite ore ± apatite ± magnetite; (2) Ti-magnetite-dominated ore; (3) Nelsonite (Fe-Ti oxides + apatite); and (4) Rutile-ilmenite ore. The stability of ilmenite and magnetite is then critically reviewed and the influence of various factors, particularly oxygen fugacity and crystallization pressure, is examined. We discuss liquidus compositions of Fe-Ti oxides and the behavior of important trace elements such as Cr and V, both of which are sensitive to fO 2 variations. Postcumulus evolution of both oxides can occur due to re-equilibration with trapped liquid, re-equilibration with ferromagnesian silicates, exsolution, oxidation, reaction between ilmenite and magnetite, and metamorphic overprinting. These various processes are described and their effects on the oxide geochemistry are emphasized. Several potential ore-forming processes have been invoked and can explain the formation of huge concentration of ilmenite, ±magnetite, ±apatite. Fractional crystallization can be combined with crystal sorting and plagioclase buoyancy to produce relative enrichment of dense ore minerals. Silicate liquid immiscibility can segregate conjugate Si-rich and Fe-rich melts, the latter being enriched in Fe-Ti-P. Magma mixing can produce hybrid magmas located in a single-phase field of the phase diagram and precipitate a pure ilmenite cumulate. Alternative processes are also described, such as ejection of Fe-Ti-enriched residual melts by filter-pressing and compaction, solidstate remobilization of ilmenite in veins, and hydrothermal transport of Fe and Ti from the host anorthosite followed by concentration in veins and lenticular ore bodies. The magnetic properties of Fe-Ti ore deposits present contrasting signatures, depending on whether the natural remanent magnetization is dominated by hemo-ilmenite or multi-domain magnetite. Micro-and macro-scale deformation features of ore rocks are intimately correlated with magma emplacement, and...

show abstract

Section: Fo 2 and Parental Magma Compositionmentioning

confidence: 99%

Section: Major Elementsmentioning

confidence: 99%

Section: Major Elementsmentioning

confidence: 99%

See 1 more Smart Citation

Fe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks

Charlier

Namur

Bolle

et al. 2015

Earth-Science Reviews

View full text Add to dashboard Cite

show abstract

“…The most commonly used and most reliable way to reconstruct magmatic fO 2 is via magnetite-ilmenite oxybarometry (e.g., Buddington and Lindsley, 1964;Carmichael, 1967;Stormer, 1983;Andersen and Lindsley, 1988;Ghiorso and Sack, 1991;Lattard et al, 2005;Ghiorso and Evans, 2008). Alternative approaches are based on (i) the Fe 2+ /Fe 3+ ratio of whole rocks (Kress and Carmichael, 1989;Putirka, 2016), (ii) mineral reactions involving olivine, pyroxene, and/or sphene Lindsley and Frost, 1992;Andersen et al, 1993;Xirouchakis et al, 2001), (iii) biotite, K-feldspar and magnetite (Wones and Eugster, 1965;Wones, 1981) , (iv) zircon Ce (and Eu) anomalies (Ballard et al, 2002;Trail et al, 2012;Smythe and Brenan, 2016), and (v) single amphibole oxybarometry (Ridolfi et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

FeTiMM – A new oxybarometer for mafic to felsic magmas

Robert¹,

Audétat²

2017

Geochem. Persp. Let.

View full text Add to dashboard Cite

The oxidation state of magmas is a key parameter that is notoriously difficult to reconstruct. The most common approach is via magnetite-ilmenite oxybarometry. However, many natural magmas do not contain ilmenite, preventing application of this technique. Here we present a new method that allows fO 2 to be reconstructed based on the partitioning of Fe and Ti between magnetite and silicate melt. The new method, which we call FeTiMM, is applicable to both ilmenite-free and ilmenite-bearing samples, and even to slowly cooled intrusive rocks such as granites. FeTiMM was calibrated on 109 experiments covering a wide range of oxygen fugacities, temperatures, pressures and silicate melts ranging from basaltic to rhyolitic composition, and returned fO 2 values that agree within 0.5 log units with independently constrained fO 2 values in all but five cases. A first test on 19 natural samples of dacitic to rhyolitic compositions was equally successful. FeTiMM thus opens the door for numerous new applications in various disciplines of Earth Sciences, including the fields of volcanology, igneous petrology, experimental geochemistry and ore geology.

show abstract

“…Unfortunately, we can perform only a very approximate estimation of PT-conditions of Al-rich magnetite exsolutions based on the models of magnetite-spinel miscibility [5,45]; however, Fe-Ti oxide geothermobarometers are much more informative. Most realistic results can be obtained using the model [49] calibrated with the cation-ordering data [51,52], and experimental data on Fe 2+ Ti ↔ 2Fe 3+ exchange between minerals of the ilmenite and spinel groups [26,53]. The model [44] can also be used for comparison.…”

Section: Introductionmentioning

confidence: 99%

Subsolidus Evolution of the Magnetite-Spinel-UlvöSpinel Solid Solutions in the Kovdor Phoscorite-Carbonatite Complex, NW Russia

et al. 2017

View full text Add to dashboard Cite

Abstract:The Kovdor phoscorite-carbonatite ore-pipe rocks form a natural series, where apatite and magnetite first gradually increase due to the presence of earlier crystallizing forsterite in the pipe marginal zone and then decrease as a result of carbonate development in the axial zone. In all lithologies, magnetite grains contain (oxy)exsolution inclusions of comparatively earlier ilmenite group minerals and/or later spinel, and their relationship reflects the concentric zonation of the pipe. The temperature and oxygen fugacity of titanomagnetite oxy-exsolution decreases in the natural rock sequence from about 500 • C to about 300 • C and from NNO + 1 to NNO − 3 (NNO is Ni-NiO oxygen fugacity buffer), with a secondary positive maximum for vein calcite carbonatite. Exsolution spinel forms spherical grains, octahedral crystals, six-beam and eight-beam skeletal crystals co-oriented with host magnetite. The ilmenite group minerals occur as lamellae oriented along {111} and {100} planes of oxy-exsolved magnetite. The kinetics of inclusion growth depends mainly on the diffusivity of cations in magnetite: their comparatively low diffusivities in phoscorite and carbonatites of the ore-pipe internal part cause size-independent growth of exsolution inclusions; while higher diffusivities of cations in surrounding rocks, marginal forsterite-rich phoscorite and vein calcite carbonatite result in size-dependent growth of inclusions.

show abstract

New calibration data for the Fe–Ti oxide thermo-oxybarometers from experiments in the Fe–Ti–O system at 1 bar, 1,000–1,300°C and a large range of oxygen fugacities

Cited by 56 publications

References 46 publications

Fe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks

Fe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks

FeTiMM – A new oxybarometer for mafic to felsic magmas

Subsolidus Evolution of the Magnetite-Spinel-UlvöSpinel Solid Solutions in the Kovdor Phoscorite-Carbonatite Complex, NW Russia

Contact Info

Product

Resources

About