J Metamorph Geol. 2019;37:889–897. wileyonlinelibrary.com/journal/jmg | 889© 2019 John Wiley & Sons Ltd

DOI: 10.1111/jmg.12505

E D I T O R I A L

Into the melting pot: A celebration of the career of Michael Brown

This Special Issue comprises a selection of the papers pre‑sented at the fifth Granulites and Granulites meeting, held in July 2018 in Ullapool, northwest Scotland. The meeting was in large part a celebration of the outstanding career contribution of Michael (Mike) Brown, who delivered the 51st Hallimond Lecture of the Mineralogical Society of Great Britain and Ireland, “Time's arrow, time's cycle: Granulite metamor‑phism and geodynamics” (Brown & Johnson, 2019a). At the time, he was halfway through his tenure as President of the Mineralogical Society of America. Mike has published more than 150 peer‐reviewed articles and book chapters, and has edited several books, mostly on topics relating to high‐grade metamorphism and crustal melting, combining petrology, structural geology, geochemistry and geochronology, to bet‑ter understand orogenic processes and global geodynamics. In the past decade or so, while pursuing several other ave‑nues of investigation, his research has focussed on identi‑fying and interpreting secular change in the metamorphic record within the context of evolving global geodynamics. Of course, the metrics related to Mike's published scientific con‑tributions are readily accessible. Less easy to quantify, but no less impactful, are his other contributions to metamorphic geology. These constitute a very long list, which includes the  organization of numerous scientific meetings, confer‑ences, symposia, short courses and workshops, time served on the boards and councils of various societies and journals, and the establishment (in 1981) of the Metamorphic Studies Group, a specialist group of the Geological Society and the Mineralogical Society of Great Britain and Ireland. However, among his most important contributions was founding (in 1982, the  first volume was published in 1983) the Journal of Metamorphic Geology, and serving as an Editor for the next three‐and‐a‐half decades. While doing all of this, he spent more than six years as a Head of School at Kingston University in the UK, and was Chair of Department at the University of Maryland in the USA for 21 years! It is difficult to think of anybody who has done quite so much to promote and sustain metamorphic geology over the past half century. The papers in this Special Issue cover a range of topics that relate to Mike's interests and expertise. It is our hope that, on reading these contributions, the reader will be stimulated to consider and question their findings, in order to better

understand metamorphic processes within the broader con‑text of Earth's geodynamic evolution.

1 | PREAMBLE

It is our pleasure to introduce the papers in this Special Issue, which celebrates the outstanding career contribution of Michael (Mike) Brown. Figure 1 shows Mike and his wife Jenny in Perth in March 2019, enjoying a glass of red after a meal––both have a passion for good food and good wine.

Mike was born in Hayes, on the western edge of London, on 19 March 1947. Figure 2a shows a three‐ or four‐year‐old Mike contemplating the best approach to constructing a sandcastle. He is pictured in Figure 2b, aged 13, with his father (Jim), mother (Ivy), younger brother (Chris), and hound (Brownie). Mike graduated in 1969, gaining a BA Honours in Geography and Geology from the University of Keele. He obtained his PhD in 1975 from the same institution for a thesis entitled ‘The Petrogenesis of the St. Malo Migmatite Belt, North‑Eastern Brittany, France’. On 5 June 1989, he married Jenny. They have three children, Matthew, Thomas, and Sarah Jane.

Through his long career, Mike has held faculty positions at the universities of Oxford Brookes and Kingston in the UK, and Maryland in the USA. He started as a lecturer at Oxford Brookes in 1972, and was Acting Head of Department just 10 years later. In 1984, Mike left to become Head of School at Kingston, where he was made Professor of Geology in 1988. In 1990, he and the family made the big decision to move to the USA, where Mike was appointed as Chair of Department at Maryland, a position he held until 2011. Despite holding these senior administrative roles, he somehow found time for a successful career in research, aspects of which are detailed below.

2 | MIKE’S RESEARCH

Before detailing some of Mike's research contributions, it is worthwhile providing some publication metrics. At the time of writing, according to Scopus, Mike has published over 140 papers that have collectively been cited more than 8,000

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times, with an h‐index of 54. In Google Scholar, his total citation count is more than 11,000, with an h‐index of 64 and an i10‐index of 129. With reference to the latter database, Mike has 36 publications that have been cited 100 times or more, of which around a third are sole‐authored works, and 18 that have been cited >150 times, with nine sole‐authored contributions.

Mike's career‐long interest in high‐T metamorphism took root during his PhD study, where he investigated the spec‑tacular migmatites exposed around the port city of St Malo in Brittany, northwest France. This and subsequent research elsewhere in the Armorican Massif clarified the petrogene‑sis of migmatites by anatexis (Brown, 1973, 1979) and es‑tablished the petrogenetic kinship between migmatites and leucogranites (Brown & D'Lemos, 1991; Brown, Power, Topley, & D'Lemos, 1990). Research driven by Mike and his co‐workers produced the first P–T–t paths from migmatite terranes (Brown, 1983; Jones & Brown, 1990) and demon‑strated the critical role of deformation in the segregation and ascent of melt through orogenic crust to the emplacement of orogenic leucogranites (D'Lemos, Brown, & Strachan, 1992). Many of these ideas are summarized in Mike's best‐cited paper, 'The generation, segregation, ascent and emplacement of granite magma: The migmatite‐to‐crustally‐derived gran‑ite connection in thickened orogens', published in 1994 in Earth‐Science Reviews (Brown, 1994). Figure 3 shows Mike on fieldwork in Cornwall in 1978.

Mike's ideas regarding the generation, segregation, and migration of melt in the crust continued to develop (Brown, Averkin, McLellan, & Sawyer, 1995), stimulated by ongoing field‐based investigations in Brittany. He also began to focus more on granulites, including the Southern Granulite Terrain (Brown & Raith, 1996; Raith, Karmakar, & Brown, 1997) and Eastern Ghats Province of India (Korhonen, Clark, Brown, Bhattacharya, & Taylor, 2013; Korhonen, Clark, Brown, &

F I G U R E 1 Mike and Jenny in downtown Perth, March 2019

F I G U R E 2 (a) A contemplative three‐ or four‐year‐old Mike; (b) with the family in 1960, aged 13

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Taylor, 2014), the Southern Brasilia Belt in Brazil (Baldwin, Powell, Brown, Moraes, & Fuck, 2005; Moraes, Brown, Fuck, Camargo, & Lima, 2002; Reno, Piccoli, Brown, & Trouw, 2012) and the Fosdick migmatite–granite complex in Marie Byrd Land, west Antarctica (Brown et al., 2016; Korhonen, Saito, Brown, Siddoway, & Day, 2010; Yakymchuk et al., 2013). Key papers examining the relationship between de‑formation, magmatism, and metamorphism stemmed from work with Gary Solar in west‐central Maine, four of which feature in the list of Mike's most cited (>150 times) papers (Brown & Solar, 1998a, 1998b, 1999; Solar & Brown, 2001), which significantly furthered our understanding of heat and mass transfer through the crust. Many of these studies were underpinned by careful petrographic observations. Figure 4 shows Mike in 2001, his hair now distinctly paler, preparing to interrogate a thin section in his lab at Maryland.

Building on the classic work of Miyashiro (1961, 1973), Mike developed ideas concerning 'paired metamorphism', confirming that paired metamorphic belts sensu stricto com‑monly were not colocated during formation, but were jux‑taposed subsequently by tectonic processes (Brown, 1998, 2002, 2010). The recognition of paired metamorphic belts as the signature of subduction stimulated Mike to examine the metamorphic rock record for evidence of secular change. Compilation of the metamorphic database, which involved

extracting the pressure (P), temperature (T) and age of (to date) more than 550 localities worldwide, was undoubtedly painstaking work, but has provided the community with an invaluable resource. Using an earlier version of this database, Mike was able to fingerprint distinct geodynamic regimes during Earth evolution, linking these to secular cooling of the Earth's mantle. Two of these papers, published in 2006 and 2007 in Geology and International Geology Review, re‑spectively, are his second and third best‐cited papers (Brown, 2006, 2007).

Expansion of the database and its statistical interroga‑tion have led to the production of three invited contributions linked to his tenure as President of the Mineralogical Society of America and the invitation to deliver the 51st Hallimond Lecture of the Mineralogical Society of Great Britain and Ireland (Brown & Johnson, 2018, 2019a, 2019b), as well as a paper, led by Robert Holder, suggesting that paired meta‑morphism, and plate tectonics, emerged gradually since the Neoarchean (Holder, Viete, Brown, & Johnson, 2019). Figure 5 shows Mike receiving a certificate following his Hallimond lecture from Simon Harley (Edinburgh), a fellow expert on granulites and ultrahigh‐temperature (UHT) metamorphism.

The geodynamic evolution of Earth, including how our planet might have behaved in the Archean Eon, has been a

F I G U R E 3 Mike on a bench in Cornwall, April 1979, aged 32 F I G U R E 4 Mike prepares to terrify a thin section in Maryland, 2001

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focus of Mike's research over the past decade. Of particular note are studies that have used numerical, phase equilibrium and trace element modelling in an attempt to decipher the geo‑dynamic styles that might have operated prior to the 'modern' plate tectonic regime (Johnson, Brown, Gardiner, Kirkland, & Smithies, 2017; Johnson, Brown, Kaus, & Vantongeren, 2014; Sizova, Gerya, & Brown, 2014; Sizova, Gerya, Brown, & Perchuk, 2010; Sizova, Gerya, Brown, & Stüwe, 2018; Sizova, Gerya, Stüwe, & Brown, 2015). However, he has con‑tinued his work on high‐grade metamorphism, with important contributions investigating open system melting and the role of accessory minerals during anatexis (Yakymchuk & Brown, 2014a, 2014b). Latterly, he has extended his interests to high‐P and ultrahigh‐pressure metamorphism of continental crust (Wang et al., 2018; Xia, Brown, Wang, Wang, & Piccoli, 2018), in particular with respect to the evolution of fluids and melts under these extreme conditions (Wang et al., 2017).

A very recent paper, published with co‐author Stephan Sobolev in Nature, extrapolates models of modern‐day plate tectonics into the past to suggest that the rise of the conti‑nents and an increasing supply of sediments to continental margins post‐3 Ga provided the lubrication required to stabi‑lize subduction (Sobolev & Brown, 2019). Furthermore, they propose that the enormous amounts of erosion that followed the Neoproterozoic 'snowball' Earth glaciations kick‐started the modern plate tectonic regime. Whether such big‐picture ideas turn out to be correct, only time will tell. However, there is little doubt that they will provoke vigorous, heated debate, a pastime that Mike holds in very great affection.

There are few people within the metamorphic community who do not know Mike. He has made it his mission to attend as many meetings and field trips as his other administrative, teaching and family commitments have permitted. He has organized, convened, and/or co‐convened around 70 scien‑tific meetings, conferences, symposia, workshops, and field

excursions, has authored more than 400 published abstracts, and delivered numerous invited lectures and seminars at in‑stitutions around the world. He was an Editor of the Journal of the Geological Society, London, from 1982 until 1986, and the founding editor of this journal, which published its first issue in 1983. After having served as an Editor of the Journal of Metamorphic Geology for 36 years, Mike eventually de‑cided to step down this year. He has been an Editor of 14 Special Issues for these and other journals, and has reviewed countless papers. He has been the principal supervisor to a dozen graduate students, some of whom have gone on to suc‑cessful careers in academia, and others whose careers have followed different paths. He has been a mentor to many more of us who have been lucky enough to find academic positions.

3 | INTO THE MELTING POT: AN INTRODUCTION TO THE PAPERS

The papers in this Special Issue, or some variant of them, were presented at the fifth Granulites and Granulites meet‑ing, held in July 2018 in Ullapool, northwest Scotland. Mike is a co‐author on two of these papers. The authors on the other contributions range from colleagues with whom Mike has interacted (and published) over many decades to others who represent the bright future of our discipline. Overall, the papers reflect the diversity of processes, scales, field areas, and approaches that has long been a hallmark of Mike's own research, and of the research he has encouraged to be pub‑lished in the Journal of Metamorphic Geology.

In the opening contribution, Yakymchuk and Brown inves‑tigate the behaviour of key heat‐producing elements (HPE) during high‐grade metamorphism. Some recent work (Alessio et al., 2018) has shown that the behaviour of the HPE during high‐T metamorphism, melting, and melt loss does not always

F I G U R E 5 Mike receiving his certificate from Simon Harley after delivering the 51st Hallimond Lecture of the Mineralogical Society of Great Britain and Ireland

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result in depletion of HPE from the source. Yakymchuk and Brown address the processes that control the distribution of HPE using a combination of phase equilibrium methods and geochemistry. They conclude that the retention of HPE, es‑pecially thorium, in the deep crust reflects the inhibition of monazite dissolution during melting or the precipitation of new monazite during melt transfer through the deep crust. Such retention may be critical to overcoming enthalpy barri‑ers to subsequent prograde reactions and to understanding the slow rates of cooling of some deep crustal granulites.

In the second paper, by Clark, Taylor, Johnson, Harley, Fitzsimons, and Oliver, a number of approaches to extracting quantitative temperatures from UHT assemblages are applied to a highly residual UHT (T > 900°C) metapelitic granulite from the Rauer Group in East Antarctica. Such rocks have long proven challenging for thermobarometry due to issues with ongoing cation exchange during cooling and challenges in developing robust thermodynamic models for minerals such as sapphirine. The study concludes that a combination of pseudosections with Al‐in‐orthopyroxene thermometry/iso‑pleths provides the most robust estimates of peak conditions. Trace element thermometry can provide useful constraints, although these may not necessarily reflect peak metamorphic conditions.

Using recently developed activity–composition models for high‐grade metabasic rocks (Green et al., 2016), the paper by Kunz and White provides new constraints on the P–T conditions and melt production along the metamorphic field gradient preserved in the Ivrea Zone. They show, using calcu‑lated pseudosections, that the metabasic rocks and metapelitic rocks return consistent P–T conditions along the studied tran‑sect. Using both metabasic and metapelitic rocks, Kunz and White define a new P–T field gradient that reflects a lower dP/dT than inferred by previous phase petrology studies.

Remaining in the Ivrea Zone, but moving to a smaller scale, Carvalho, Bartoli, Ferri, Cesare, Ferrero, Remusat, Capizzi, and Poli present a detailed study of coexisting in‑clusions of nanogranite and fluid preserved within garnet in metapelitic migmatites to investigate the evolving composi‑tion of melt and fluid during amphibolite to granulite facies metamorphism. At all metamorphic grades, the preserved fluids are compositionally similar and comprise mixtures of CO2, CH, and N2. Rehomogenization of the nanogranite in‑clusions indicates that, with increasing metamorphic grade, the melts generally have lower H2O contents but higher con‑centrations of CaO and FeO+MgO. Of particular interest are the CO2 concentrations, which increase with metamorphic grade. The authors interpret these data as evidence for melt‑ing by reactions consuming mica in the presence of a car‑bonic fluid that was internally derived.

In the paper by Mitchell, Johnson, Clark, Gupta, Brown, Harley, and Taylor, an integrated microstructural, thermo‑dynamic, and geochronological approach is adopted in an

attempt to unravel the evolution of complex UHT granulites from the Eastern Ghats province in India. The samples are strongly domanial, suggesting small diffusive length scales even under UHT conditions. The study establishes that the area was affected by two metamorphic events, a protracted Neoproterozoic UHT event in which high temperatures per‑sisted for > or >>100 Ma, and a later Cambrian event. These results are used to build a larger scale tectonic model for the Eastern Ghats and neighbouring crustal blocks.

Equilibration volumes are also among the topics cov‑ered in the sixth paper, in which Powell, Evans, Green, and White outline the important but commonly overlooked role that chemical potential plays in much of our understanding of metamorphic equilibrium and equilibration. Although chem‑ical potential is a well‐defined thermodynamic variable, its use in understanding metamorphism and metamorphic rocks is underappreciated. This contribution outlines the role chem‑ical potential plays in many common metamorphic ideas and processes such as diffusion, reaction textures, and volumes of equilibration. The idea of chemical potential as a spatial entity in metamorphic rocks is explored in terms of chemical potential landscapes that evolve as conditions change.

The relationships between metamorphic reactions and deformation are investigated in the paper by Chapman, Clarke, Piazolo, Robbins, and Trimby. The study concen‑trates on the evolution of metaigneous rocks from Fiordland, New Zealand, where the primary igneous minerals and mi‑crostructures are variably transformed into eclogite facies assemblages. Detailed electron backscattered diffraction analysis identifies domains of enhanced crystal‐plastic de‑formation that correspond to regions of enhanced reaction, reinforcing the important coupling between metamorphism and deformation.

F I G U R E 6 Mike carefully examining a rock in Dabieshan, China

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In the final contribution, Higashino, Rubatto, Kawakami, Bouvier, and Baumgartner use high‐precision in situ phos‑phorus and oxygen isotope analysis of a garnet porphyroblast to constrain the processes of high‐T metamorphism in the Sør Rondane Mountains in East Antarctica. The analysis reveals a discontinuous stepwise zoning in phosphorus from a high‐phosphorus core to a low‐phosphorus rim, coupled with a more continuous variation in δ18O from core to rim. They in‑terpret this oxygen isotope pattern to reflect modification of an original stepwise boundary during a ~800°C metamorphic event that lasted for 0.5–40 Ma.

4 | CLOSING REMARKS

There is almost nobody in the metamorphic community who has not interacted with Mike in some way either through the Journal of Metamorphic Geology, at a conference, or in the field. For most of us, our first experience of Mike was in the form of a booming voice asking a pertinent, often tricky question, at the end of a talk. Worse still, that encounter came at the end of one's own talk. He is well known for keeping the scientific discourse at conferences and on field trips as lively as his shirts, and is certainly not one to leave any of us wondering as to his scientific views on any given subject or outcrop. Figure 6 shows Mike on a field trip in the Dabieshan associated with a short course in Wuhan, China, examining a sample closely with his trusty hand lens, possibly with a view to starting an argument.

Since stepping down from the Chair at Maryland in 2011, and now approaching the age of 73, Mike has shown no signs of slowing down. Quite the opposite. We look forward to reading more of Mike's papers in the years to come, and hearing, quite clearly, what he has to say on a range of is‑sues. Mike takes his science extremely seriously. However, as shown in Figure 7, there are at least two things that can make him smile. The first (Figure 7a) is self‐explanatory. So is the second (Figure 7b).

We end with some apposite lyrics, based on the song 'Bad Bad Leroy Brown' by American folk‐rock singer Jim Croce, which were written and performed by Simon Harley at the 2018 Granulites and Granulites conference dinner:

Bad Bad Michael Brown

Oh the north side of Saint MaloIs the hottest part of townAnd if you go down there you'd better just bewareOf a man named Michael Brown

Now Michael's more than troubleYou see he likes to cause a stirAll the other geos call him 'Migmatite Mike'And all his students call him 'Sir'

Cause he's hot, hot Michael BrownHottest man in the whole damn townHotter than amphiboliteMolten as a migmatite

Now Michael, he's a MetmanAnd he likes some fancy stonesAnd he like to talk ‘bout partial meltingIn front of everybody's noseHe's gone supercontinental

F I G U R E 7 (a) Mike flicking through Working with Migmatites, which he edited with Ed Sawyer; (b) at Siple Dome, Antarctica, Mike appears satisfied with the subdivision of the rations

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Cause he likes his granulites tooHe got a big computer full of coupled modelsHe gonna tell you ‘bout them too

Cause he's loud, loud Michael BrownLoudest man in the whole damn townDoesn't need a microphoneLoud enough on his own

Now way back in the ninetiesSampling Palni with Mike RaithAt the edge of the outcropWas a sapphirine granuliteAnd ooh that rock was nice (gneiss)Well he cast his eyes upon itAnd the trouble was there to seeMichael Brown then found himself a messin’With the world of UHT

Cause he's hot, hot Michael BrownHottest man in the whole damn townHotter than amphiboliteMolten as a migmatite

Cause he's hot, hot Michael BrownHottest man in the whole damn townHotter than most UHTFounder of the JMG

ACKNOWLEDGEMENTS

We thank the authors for meeting our schedule for submis‑sion and revision of manuscripts, and the reviewers for their prompt and constructive reviews. We are grateful to Jenny Brown for supplying some of the photographs, and to both her and Mike for helping us pinpoint times and places. T.E.J. is indebted to Kevin Murphy and Russell Rajendra at the Mineralogical Society of Great Britain and Ireland for their help and support in organizing the 2018 Granulites and Granulites conference. We are grateful to the publishers of the Journal of Metamorphic Geology for their generous sponsorship of the icebreaker.

Tim E. Johnson1,2

Richard W. White3

Chris Clark1

1School of Earth and Planetary Sciences,  The Institute for Geoscience Research, Curtin University,

Perth, WA, Australia2State Key Laboratory for Geological Processes and Mineral Resources and Center for Global Tectonics,

School of Earth Sciences, China University of Geosciences, Wuhan, China

3School of Earth & Environmental Sciences,  University of St Andrews, St Andrews, UK

CorrespondenceTim E. Johnson, School of Earth and Planetary Sciences, The Institute for Geoscience Research, Curtin University,

Perth, WA, Australia.Email: tim.johnson@curtin.edu.au

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Baldwin, J. A., Powell, R., Brown, M., Moraes, R., & Fuck, R. A. (2005). Modelling of mineral equilibria in ultrahigh‐temperature metamorphic rocks from the Anápolis‐Itauçu Complex, central Brazil. Journal of Metamorphic Geology, 23(7), 511–531. https ://doi.org/10.1111/j.1525‑1314.2005.00591.x

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Korhonen, F. J., Saito, S., Brown, M., Siddoway, C. S., & Day, J. M. D. (2010). Multiple generations of granite in the Fosdick Mountains, Marie Byrd Land, West Antarctica: Implications for polyphase intracrustal differentiation in a continental margin setting. Journal of Petrology, 51(3), 627–670. https ://doi.org/10.1093/petro logy/egp093

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Moraes, R., Brown, M., Fuck, R. A., Camargo, M. A., & Lima, T. M. (2002). Characterization and P‐T evolution of melt‐bearing ultrahigh‐temperature granulites: An example from the Anápolis‐Itauçu Complex of the brasília fold belt, Brazil. Journal of Petrology, 43(9), 1673–1705.

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Sizova, E., Gerya, T., & Brown, M. (2014). Contrasting styles of Phanerozoic and Precambrian continental collision. Gondwana Research, 25(2), 522–545. https ://doi.org/10.1016/j.gr.2012.12.011

Sizova, E., Gerya, T., Brown, M., & Perchuk, L. L. (2010). Subduction styles in the Precambrian: Insight from numerical experiments. Lithos, 116(3–4), 209–229. https ://doi.org/10.1016/j.lithos. 2009.05.028

Sizova, E., Gerya, T., Brown, M., & Stüwe, K. (2018). What drives metamorphism in early Archean greenstone belts? Insights from numerical modeling. Tectonophysics, 746, 587–601. https ://doi.org/ 10.1016/j.tecto.2017.07.020

Sizova, E., Gerya, T., Stüwe, K., & Brown, M. (2015). Generation of felsic crust in the Archean: A geodynamic modeling perspective. Precambrian Research, 271, 198–224. https ://doi.org/10.1016/ j.preca mres.2015.10.005

Sobolev, S. V., & Brown, M. (2019). Surface erosion events controlled the evolution of plate tectonics on Earth. Nature, 570(7759), 52. https ://doi.org/10.1038/s41586‑019‑1258‑4

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Wang, L., Wang, S. J., Brown, M., Zhang, J. F., Feng, P., & Jin, Z. M. (2018). On the survival of intergranular coesite in UHP eclogite. Journal of Metamorphic Geology, 36(2), 173–194. https ://doi.org/ 10.1111/jmg.12288

Wang, S.‐J., Wang, L., Brown, M., Piccoli, P. M., Johnson, T. E., Feng, P., … Huang, Y. (2017). Fluid generation and evolution during exhumation of deeply subducted UHP continental crust: Petrogenesis of composite

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granite–quartz veins in the Sulu belt, China. Journal of Metamorphic Geology, 35(6), 601–629. https ://doi.org/10.1111/jmg.12248

Xia, B., Brown, M., Wang, L., Wang, S.‐J., & Piccoli, P. (2018). Phase equilibrium modeling of MT–UHP eclogite: A case study of coesite eclogite at Yangkou Bay, Sulu belt, Eastern China. Journal of Petrology, 59(7), 1253–1280. https ://doi.org/10.1093/ petro logy/egy060

Yakymchuk, C., & Brown, M. (2014a). Behaviour of zircon and monazite during crustal melting. Journal of the Geological Society, 171(4), 465–479. https ://doi.org/10.1144/jgs20 13‑115

Yakymchuk, C., & Brown, M. (2014b). Consequences of open‐system melting in tectonics. Journal of the Geological Society, 171(1), 21–40. https ://doi.org/10.1144/jgs20 13‑039

Yakymchuk, C., Siddoway, C. S., Fanning, C. M., McFadden, R., Korhonen, F. J., & Brown, M. (2013). Anatectic reworking and differentiation of continental crust along the active margin of Gondwana: A zircon Hf‐O perspective from West Antarctica. Geological Society Special Publication, 383, 169–210.

How to cite this article: Johnson TE, White RW, Clark C. Into the melting pot: A celebration of the career of Michael Brown. J Metamorph Geol. 2019;37:889–897. https ://doi.org/10.1111/jmg.12505