Tracking the Ti⁴⁺ substitution in phlogopite by spectroscopic imaging: A tool for unravelling the growth of micas at HP-HT conditions

Abstract

Phlogopite solid-solutions have a wide pressure–temperature (P-T) stability field and are ubiquitous in a wide variety of geological settings, from deep lithosphere magmatic environments to upper crust metamorphic domains. Phlogopite composition represents therefore a valuable physical–chemical archive and may provide important information regarding its crystallization and the petrogenesis of the host-rock. In this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from St. Helier (Island of Jersey, UK). Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning, however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti (average TiO₂ ≈ 8.5 wt.%) cores enveloped by euhedral low- to mid-amplitude zonation due to oscillatory contents in Ti, Fe and Mg. Thermo-barometry modelling based on biotite-only composition yields relatively high P-T estimates (T ≈ 970 ± 54 °C at P ≈ 0.73 ± 0.13 GPa) for cores whereas lower values (T ≈ 790 ± 54 °C at P ≈ 0.29 ± 0.13 GPa) are obtained for the outer rims. Comparable temperatures (T ≈ 1075 ± 54 °C) but extremely high and anomalous pressure values (P ≈ 1.82 ± 0.13 GPa) are obtained for the yellowish inner rims. The combination of electron micro probe (EMP) analysis and single-crystal infra-red (FTIR) imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution, typical of crystallization and growth processes of HP/HT environments. Raman imaging provides additional insight for this process, confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer rims. Interpretation of thermobaric estimates obtained from the phlogopite composition-only model, based on the fine-scale compositional evolution, shows that pressure–temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocally related to pressure–temperature variation of the crystallizing environment. Our results demonstrate how a multidisciplinary approach based on the combination of chemical investigations and vibrational spectroscopies could represent a valuable tool to evaluate pressure–temperature estimates from biotite composition-only thermo-barometry models and therefore to correctly unravel HP/HT petrogenetic processes at a very fine scale.

Keywords

Ti-phlogopite / Jersey minette (UK) / Ti-substitution / FTIR imaging / Raman imaging / Thermobarometric modelling

CRediT authorship contribution statement

Feiyu Zhao: Writing – review & editing, Writing – original draft, Software, Methodology, Formal analysis, Data curation. Sanzhong Li: Writing – review & editing, Funding acquisition, Conceptualization. Yanhui Suo: Writing – review & editing, Supervision, Conceptualization. Juzhi Deng: Funding acquisition, Writing – review & editing. Mengxue Dai: Funding acquisition, Writing – review & editing. Xiao Chen: Methodology, Writing – review & editing. Bin Hu: Investigation, Writing – review & editing. Yanguo Wang: Methodology, Software, Writing – review & editing. Yaping Hu: Writing – review & editing.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

Critical and constructive comments from the editors and anonymous reviewers significantly improved the quality of the manuscript. This research was financially supported by the National Natural Science Foundation of China (Grant Nos. 42462024, 42304145, 42121005 and 42130811) and the Jiangxi Provincial Natural Science Foundation (Grant Nos. 20242BAB25182, 20242BAB27002). This study was also supported by the Opening Foundation of Key Lab of Submarine Geosciences and Prospecting Techniques, Ocean University of China (SGPT-20240F-01). This study used Geosoft and Oasis Montaj Software to analyze gravity data. Most figures were made using GMT (Wessel et al., 2019).

References

J. Abrecht, D.A. Hewitt. Experimental evidence on the substitution of Ti in biotite. Am. Mineral., 73 (1988), pp. 1275-1284

M. Arima, A.D. Edgar. Substitution mechanisms and solubility of titanium in phlogopites from rocks of probable mantle origin. Contrib. Mineral. Petr., 77 (1981), pp. 288-295

S. Aspiotis, J. Schlüter, G.J. Redhammer, B. Mihailova. Non-destructive determination of the biotite crystal-chemistry using Raman spectroscopy: how far can we go?. Eur. J. Mineral., 34 (2022), pp. 573-590,

Baidya, A.S., Das, E., 2022. “Calculating biotite formula from electron microprobe analysis data using a machine learning method based on principal components regression” by Li et al. (Lithos 356–357 (2020) 105371) - A discussion. Lithos 412, 106334.

A. Bendeliani, N.N. Eremin, A. Bobrov. Mechanisms and conditions of Ti and Cr incorporation in mantle phlogopite: the results of atomistic simulation. Phys. Chem. Miner., 50 (2023),

Beran, A., 2002. Infrared spectroscopy of micas. In: Mottana, A., Sassi, F.P., Thompson, J.B. jr., Guggenheim, S. (Eds.). Micas: crystal chemistry and metamorphic petrology. Reviews in Mineralogy and Geochemistry 46, Mineralogical Society of America, Chantilly (Virginia, USA), pp. 351-369.

S. Bernardini, G. Della Ventura, A. Sodo, M. Benites, L. Jovane, J.R. Hein, F. Lucci. Micro-Raman mapping of critical metals (Li Co, Ni) in a rhythmically laminated deep-ocean ferromanganese deposit. Geochemistry, 126014 (2023),

A.L. Boettcher, J.R. O’Neil, K.E. Windom, D.C. Stewart, H.G. Wilshire. Metasomatism of the upper mantle and the genesis of kimberlites and alkali basalts. F.R. Boyd, H.O.A. Meyer (Eds.), The Mantle Sample: Inclusions in Kimberlite and Other Volcanics, American Geophysical Union, Washington (USA) (1979), pp. 173-182

B. Boukili, F. Holtz, J.-L. Robert, M. Joriou, J.-M. Bény, M. Naji. Infrared spectra of annite in the O-H stretching vibrational range. Schweiz. Mineral. Petrogr. Mitt., 83 (2003), pp. 331-340

A. Brandelik. CALCMIN–an EXCEL™ Visual Basic application for calculating mineral structural formulae from electron microprobe analyses. Comput. Geosci., 35 (2009), pp. 1540-1551,

Brigatti, M.F., Guggenheim, S., 2002. Micas crystal chemistry and the influence of pressure, temperature, and solid solution on atomistic models. In: Mottana, A., Sassi, F.P., Thompson, J.B. jr., Guggenheim, S. (Eds.) Micas: crystal chemistry and metamorphic petrology. Reviews in Mineralogy and Geochemistry 46, Mineralogical Society of America, Chantilly (Virginia, USA), pp. 1-98.

B. Cesare, G. Cruciani, U. Russo. Hydrogen deficiency in Ti-rich biotite from anatectic metalelites (El Joyazo, SE Spain): crystal-chemical aspects and implications for high-temperature petrogenesis. Am. Mineral., 88 (2003), pp. 583-595

G. Cruciani, P.F. Zanazzi. Cation partitioning and substitution mechanisms in 1 M phlogopite: a crystal chemical study. Am. Mineral., 79 (1994), pp. 289-301

G. Della Ventura, A. Marcelli, F. Bellatreccia. SR-FTIR microscopy and FTIR imaging in the Earth Sciences. G.S. Henderson, D.R. Neuville, R.T. Downs (Eds.), Spectroscopic Methods in Mineralogy and Material Sciences. Reviews in Mineralogy and Geochemistry 78, Mineralogical Society of America, Chantilly (Virginia, USA) (2014), pp. 447-479

D.F. Dooley, A.E. Patiño Douce. Fluid-absent melting of F-rich phlogopite+ rutile+ quartz. Am. Miner., 81 (1996), pp. 202-212

R.F. Dymek. Titanium, aluminum and interlayer cation substitutions in biotite from high-grade gneisses, west Greenland. Am. Mineral., 68 (1983), pp. 880-899

A.D. Edgar, L.A. Pizzolato. An experimental study of partitioning of fluorine between K-richterite, apatite, phlogopite, and melt at 20 kbar. Contrib. Mineral. Petr., 121 (1995), pp. 247-257,

N. El Moutouakkil, B. Boukili. Interactions chimiques au niveau d’une interface micacée: cas des phlogopites magmatiques zonée de la minette de l’île de Jersey. Bullettin De La Société Des Sciences De Liège, 84 (2015), pp. 175-193

A.J. Engel, C.G. Engel. Progressive metamorphism and granitization of the major paragneiss, northwest Adirondack Mountains, New York. Part II: mineralogy. Geol. Soc. Am. Bull., 71 (1960), pp. 1-58

V.C. Farmer, B. Velde. Effect of structural order and disorder on the infrared spectra of brittle micas. Mineral. Mag., 39 (1973), pp. 282-288

Farmer, V.C. The layer silicates. In: Farmer V.C. (Ed.), The infrared spectra of minerals. Mineralogical Society London, 539 pp.

S.F. Foley. Experimental constraints on phlogopite chemistry in lamproites: 2. Effect of pressure-temperature variations. Eur. J. Mineral., 2 (1990), pp. 327-341

W.C. Forbes, M.F.J. Flower. Phase relations of titan-phlogopite, K2(Mg4Ti)(Si6Al2)O20(OH)2: a refractory phase in the upper mantle?. Earth Planet Sci. Lett., 22 (1974), pp. 60-66

B.R. Frost. Introduction to oxygen fugacity and its petrologic importance. Rev. Mineral. Geochem., 25 (1991), pp. 1-9

C.V. Guidotti, M.D. Dyar. Ferric iron in metamorphic biotite and its petrologic and crystallochemical implications. Am. Mineral., 76 (1991), pp. 161-175

Guidotti, C.V., 1984 Micas in metamorphic rocks. In: Bailey, S.W. (Ed.), Micas. Reviews in Mineralogy 13, Mineralogical Society of America, Chantilly (Virginia, USA), pp. 357-468.

B. Güttler, W. Niemann, S.A. Redfern. EXAFS and XANES spectroscopy study of the oxidation and deprotonation of biotite. Mineral. Mag., 53 (1989), pp. 591-602

G.E. Harlow, R. Davies. Status report on stability of K-rich phases at mantle conditions. Lithos, 77 (2004), pp. 647-653,

C.M.B. Henderson, K.A. Foland. Ba-and Ti-rich primary biotite from the Brome alkaline igneous complex, Monteregian Hills, Quebec; mechanisms of substitution. Can. Mineral., 34 (1996), pp. 1241-1252

D.J. Henry, C.V. Guidotti, J.A. Thomson. The Ti-saturation surface for low-to- medium pressure metapelitic biotites: Implications for geothermometry and Ti- substitution mechanisms. Am. Mineral., 90 (2005), pp. 316-328

C. Jin, X.-Y. Gao, W.T. Chen, T.-P. Zhao. Magmatic-hydrothermal evolution of the Donggou porphyry Mo deposit at the southern margin of the North China Craton: evidence from chemistry of biotite. Ore Geol. Rev., 92 (2018), pp. 84-96,

V.C. Kress, I.S.E. Carmichael. The compressibility of silicate liquids containing Fe2O3 and the effect of composition, temperature, oxygen fugacity and pressure on their redox states. Contrib. Mineral. Petr., 108 (1991), pp. 82-92

G.O. Lepore, L. Bindi, G. Pedrazzi, S. Conticelli, P. Bonazzi. Structural and chemical variations in phlogopite from lamproitic rocks of the central Mediterranean region. Lithos, 286–287 (2017), pp. 191-205

X. Li, C. Zhang. Machine learning thermobarometry for biotite-bearing magmas. J. Geophys. Res.: Solid Earth, 127 (2022), p. e2022,

X. Li, C. Zhang, H. Behrens, F. Holtz. Calculating biotite formula from electron microprobe analysis data using a machine learning method based on principal components regression. Lithos, 356–357 (2020), Article 105371,

E. Libowitzky, G.R. Rossman. An IR calibration for water in minerals. Am. Mineral., 82 (1997), pp. 1111-1115

F. Lucci, G. Carrasco-Núñez, F. Rossetti, T. Theye, J.C. White, S. Urbani, H. Azizi, Y. Asahara, G. Giordano. Anatomy of the magmatic plumbing system of Los Humeros Caldera (Mexico): implications for geothermal systems. Solid Earth, 11 (2020), pp. 125-159

E. Mesto, E. Schingaro, F. Scordari, L. Ottolini. An electron microprobe analysis, secondary ion mass spectrometry, and single-crystal X-ray diffraction study of phlogopites from Mt. Vulture, Potenza, Italy: considerations of cation partitioning. Am. Mineral., 91 (2006), pp. 182-190

J.L. Munoz, S. Ludington. F1uorine-hydroxyl exchange in biotite. Am. J. Sci., 274 (1974), pp. 396-413

A.E. Patiño Douce. Titanium substitution in biotite: an empirical model with applications to thermometry, O2 and H2O barometries, and consequences for biotite stability. Chem. Geol., 108 (1993), pp. 133-162

F. Prechtel, R. Stalder. FTIR spectroscopy with a focal plane array detector: a novel tool to monitor the spatial OH-defect distribution in single crystals applied to synthetic enstatite. Am. Mineral., 90 (2010), pp. 1636-1640

Putirka, K.D., 2008. Thermometers and barometers for volcanic systems. In: Putirka, K.D., Tepley F.J. III (Eds.) Minerals, inclusions and volcanic processes. Reviews in Mineralogy and Geochemistry 69, Mineralogical Society of America, Chantilly (Virginia, USA), pp. 61-120.

G.J. Redhammer, A. Beran, J. Schneider, G. Amthauer, W. Lottermoser. Spectroscopic and structural properties of synthetic micas on the annite-siderophyllite binary: synthesis, crystal structure refinement, mossbauer, and infrared spectroscopy. Am. Mineral., 85 (2000), pp. 449-465

J.-L. Robert. Titanium solubility in synthetic phlogopite solid solutions. Chem. Geol., 17 (1976), pp. 213-227

J.-L. Robert, J.-M. Beny, C. Beny, M. Volfinger. Characterization of lepidolites by Raman and infrared spectrometries. I. Relationships between OH-stretching wavenumbers and composition. Can. Mineral., 27 (1989), pp. 225-235

J.-L. Robert, J.-M. Bény, G. Della Ventura, M. Hardy. Fluorine in micas: crystal-chemical control of the OH-F distribution between trioctahedral and dioctahedral sites. Eur. J. Mineral., 5 (1993), pp. 7-18

J.-L. Robert, H. Kodama. Generalization of the correlation between hydroxyl-stretching wavenumbers and composition of micas in the system K2O-MgO-Al2O3-SiO2-H2O: a single model for dioctahedral and trioctahedral micas. Am. J. Sci., 288A (1998), pp. 196-212

M.J. Rutherford. The phase relations of aluminous iron biotites in the system KAlSi3O8-KAlSiO4-Al2O3-Fe-O-H. J. Petr., 14 (1973), pp. 159-180,

R. Sassi, G. Cruciani, C. Mazzoli, L. Nodati, J. Craven. Multiple titanium substitutions in biotite from high-grade metapelitic xenoliths (Euganean Hills, Italy): complete crystal-chemistry and appraisal of petrologic control. Am. Mineral., 93 (2008), pp. 339-350

E. Schingaro, F. Scordari, E. Mesto, M.F. Brigatti, G. Pedrazzi. Cation-site partitioning in Ti-rich micas from Black Hill (Australia): a multi-technical approach. Clay Clay Miner., 53 (2005), pp. 179-189

E. Schingaro, F. Scordari, S. Matarrese, E. Mesto, F. Stoppa, G. Rosatelli, G. Pedrazzi. Phlogopite from the Ventaruolo subsynthem volcanics (Mt. Vulture, Italy): a multi-method study. Mineral. Mag., 71 (2007), pp. 519-537

F. Scordari, G. Ventruti, A. Sabato, F. Bellatreccia, G. Della Ventura, G. Pedrazzi. Ti-rich phlogopite from Mt. Vulture (Potenza, Italy) investigated by a multianalytical approach: substitutional mechanisms and orientation of the OH dipoles. Eur. J. Mineral., 18 (2006), pp. 379-391

A.A. Sepahi, F. Lucci, S. Shakiba, K. Nakashima, H. Vahidpour. Understanding the magma-crust interaction: the role of the northern Gondwana margin in the genesis and evolution of the Jurassic Alvand plutonic complex (Sanandaj-Sirjan Zone, NW Iran). J. Afr. Earth Sci., 205 (2023), Article 104998,

H. Skogby, G.R. Rossman. The intensity of the amphibole OH bands in the Infrared absorption spectrum. Phys. Chem. Miner., 18 (1991), pp. 64-68

Streck, M.J., 2008. Mineral textures and zoning as evidence for open system processes. In: Putirka, K.D., Tepley F.J. III (Eds.), Minerals, inclusions and volcanic processes. Reviews in Mineralogy and Geochemistry 69, Mineralogical Society of America, Chantilly (Virginia, USA), pp. 595-622.

A. Tlili, D.C. Smith, J.-M. Beny, H. Boyer. A Raman microprobe study of natural micas. Mineral. Mag., 53 (1989), pp. 165-179

R.G. Trønnes. Stability range and decomposition of potassic richterite and phlogopite end members at 5–15 GPa. Mineral. Petr., 74 (2002), pp. 129-148

L. Turpin, D. Velde, G. Pinte. Geochemical comparison between minettes and kersantites from the western European Hercynian orogen: trace element and Pb–Sr–Nd isotope constraints on their origin. Earth Planet. Sci. Lett., 87 (1988), pp. 73-86

T. Ubide, C. Galé, P. Larrea, E. Arranz, M. Lago. Antecrysts and their effect on rock compositions: the Cretaceous lamprophyre suite in the Catalonian Coastal Ranges (NE Spain). Lithos, 206 (2014), pp. 214-233

E. Uchida, S. Endo, M. Makino. Relationship between solidification depth of granitic rocks and formation of hydrothermal ore deposits. Resour. Geol., 57 (2007), pp. 47-56

W. Vedder. Correlation between infrared spectrum and chemical composition of mica. Am. Mineral., 49 (1964), pp. 736-768

D. Velde. Les micas des lamprophyres: kersantites, minettes et lamproites. Bullettin Société Française De Minéralogie Et De Cristallographie, 92 (1969), pp. 203-223

D. Velde. Les lamprophyres á feldspath alcalin et biotite: minettes et roches voisines. Contrib. Mineral. Petr., 30 (1971), pp. 216-239

C. Wagner, D. Velde. Mineralogy of two peralkaline, arfvedsonite-bearing minettes. A new occurrence of Zn-rich chromite. Bull. Minéralogié, 108 (1985), pp. 173-187

A. Wang, J.J. Freeman, L.J. Bradley. Understanding the Raman spectral features of phyllosilicates. J. Raman Spectrosc., 2015 (2015),

D.J. Waters, N.R. Charnley. Local equilibrium in polymetamorphic gneiss and the titanium substitution in biotite. Am. Mineral., 87 (2002), pp. 383-396

G.A. Waychunas. Synchrotron radiation XANES spectroscopy of Ti in minerals: effect of Ti bonding distances, Ti valence, and site geometry on absorption edge structure. Am. Mineral., 72 (1987), pp. 89-101

D.R. Wones, H.P. Eugster. Stability of biotite: experiment, theory and applications. Am. Mineral., 50 (1965), pp. 1228-1272

B.J. Wood, J. Nicholls. The thermodynamic properties of reciprocal solid solutions. Contrib. Mineral. Petr., 66 (1978), pp. 389-400

C.M. Wu, H.X. Chen. Revised Ti-in-biotite geothermometer for ilmenite- or rutile-bearing crustal metapelites. Sci. Bull., 60 (2015), pp. 116-121,

F. Yavuz. Evaluating micas in petrologic and metallogenic aspect: I–definitions and structure of the computer program MICA+. Comput. Geosci., 29 (2003), pp. 1203-1213,

F. Yavuz, T. Öztaş. BIOTERM—A program for evaluating and plotting microprobe analyses of biotite from barren and mineralized magmatic suites. Comput. Geosci., 23 (1997), pp. 897-907,

C. Zhang, J. Koepke, L.X. Wang, P.E. Wolff, S. Wilke, A. Stechern, R. Almeev, F. Holtz. A practical method for accurate measurement of trace level fluorine in Mg- and Fe-bearing minerals and glasses using electron probe microanalysis. Geostand. Geoanal. Res., 40 (2016), pp. 351-363

M. Zhang, P. Suddaby, R.N. Thompson, M.A. Dungan. Barian titanian phlogopite from potassic lavas in northeast China: chemistry, substitutions, and paragenesis. Am. Mineral., 78 (1993), pp. 1056-1065