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Mineralogy and crystallization history of a highly differentiated REE-enriched hypabyssal rhyolite: Round Top laccolith, Trans-Pecos, Texas

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Abstract

The Round Top hypabyssal rhyolite laccolith is a highly evolved magmatic system, enriched in incompatible elements including REE [Rare Earth Element(s)], U, Be, and F. The Round Top intrusion is part of a series of Paleogene intrusions emplaced as the Sierra Blanca Complex. These intrusions are situated within long-lived, complex tectonic regimes that have been subjected to regional compression and subduction, punctuated by extensional bimodal volcanism. The enrichment in the rhyolite that comprises Round Top is the result of the prolonged removal of compatible elements from the source magma chamber through the emplacement of earlier magmatic events. With the emplacement of each sequential laccolith, the F-rich source magma became more enriched in incompatible elements, with increasing HREE [Heavy Rare Earth Elements(s)] concentrations. The emplacement of Round Top as a laccolith (versus that of an extrusive rhyolitic flow) facilitated the retention of the volatile-rich vapor phase within the magma, forming ubiquitous REE-bearing minerals, mainly yttrofluorite and yttrocerite. The high temperature mineral-vapor phase alteration of the feldspar groundmass was essential to the formation of REE minerals, where the pervasive open pore space was occupied by the late-crystallizing minerals. These late-forming REE-bearing minerals also occur as crystals associated with other accessory and trace phases, as inclusions within other phases, along grain boundaries, and along fractures and within voids. The rhyolite at Round Top and other laccolith intrusions in the Sierra Blanca Complex represent a new sub-type of magmatic rare earth element hosting system.

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References

  • Albritton CC Jr, Smith JF Jr (1965) Geology of the Sierra Blanca area, Hudspeth County, Texas. Geol Surv Prof Pap, vol 479. US Geol Surv, Washington DC, 131 pp

  • Barker DS (1977) Northern Trans-Pecos magmatic province: introduction and comparison with the Kenya rift. Geol Soc Am Bull 88(10):1421–1427

    Article  Google Scholar 

  • Barker DS (1979) Magmatic evolution in the Trans-Pecos province. In: Walton AW, Henry CD (eds) Cenozoic geology of the Trans-Pecos volcanic field of Texas. Bureau of Economic Geology, University of Texas at Austin, Guidebook 19, pp 4–9

  • Barker DS (1980) Cenozoic igneous rocks, Sierra Blanca area, Texas. In: Dickenson PW, Hoffer JM, Callender JF (eds) Trans-Pecos region, southeastern New Mexico and West Texas. New Mexico Geol Soc Guidebook, 31st Field Conference, pp 219–223

  • Barker DS (1987) Tertiary alkaline magmatism in Trans-Pecos Texas. In: Fitton JG, Upton BGJ (eds) Alkaline igneous rocks, vol 30. Geol Soc London Spec Pub, pp 415–431

  • Boynton WV (1984) Geochemistry of the rare earth elements: meteorite studies. In: Henderson P (ed) Rare earth element geochemistry. Elsevier, Amsterdam, pp 63–114

    Chapter  Google Scholar 

  • Burgisser A, Scaillet B (2007) Redox evolution of a degassing magma rising to the surface. Nature 445:194–197

    Article  Google Scholar 

  • Corry CE (1988) Laccoliths; mechanics of emplacement and growth. Geol Soc Am Spec Pap, vol 220. Geological Soc Am, Boulder, 114 pp

  • Giordano D, Romano C, Dingwell DB, Poe B, Behrens H (2004) The combined effects of water and fluorine on the viscosity of silicic magmas. Geochim Cosmochim Ac 68(24):5159–5168

    Article  Google Scholar 

  • Hammer JE, Rutherford MJ (2002) An experimental study of the kinetics of decompression-induced crystallization in silicic melt. J Geophys Res 107(B1):1–24

    Article  Google Scholar 

  • Henry CD, McDowell FW (1986) Geochronology of magmatism in the Tertiary volcanic field, trans-Pecos Texas. Bureau of Economic Geology, University of Texas at Austin, guidebook no 23:99–122

    Google Scholar 

  • Henry CD, Price JG (1984) Variations in caldera development in the Tertiary volcanic field of trans-Pecos Texas. J Geophys Res 89(B10):8765–8786

    Article  Google Scholar 

  • Henry CD, Price JG, James EW (1991) Mid-Cenozoic stress evolution and magmatism in the southern Cordillera, Texas and Mexico; transition from continental arc to intraplate extension. J Geophys Res 96(B8):13

    Article  Google Scholar 

  • Henry CD, Price JG, Miser DE (1989) Geology and tertiary igneous activity of the Hen Egg Mountain and Christmas Mountains quadrangles, Big Bend region, Trans-Pecos Texas. Bureau of Economic Geology, University of Texas at Austin, Report of investigators, vol 183, 105 pp

  • Hulse DE, Newton MC III, Malhotra D (2013) NI 43–101 preliminary economic assessment, Round Top project, Sierra Blanca, Texas. Texas Rare Earth Resources Corp, Sierra Blanca, 196 pp

    Google Scholar 

  • Johan Z, Johan V (2005) Accessory minerals of the Cínovec (Zinnwald) granite cupola, Czech Republic: indicators of petrogenetic evolution. Mineral Petrol 83:113–150

    Article  Google Scholar 

  • Lisowiec K, Buzyn B, Slaby E, Renno AD, Götze J (2012) Fluid-induced magmatic and post-magmatic zircon and monazite patterns in granitoid pluton and related rhyolitic bodies. Chem Erde–Geochem 73(2):163–179

    Google Scholar 

  • London D (2014) Subsolidus isothermal fractional crystallization. Am Mineral 99:543–546

    Article  Google Scholar 

  • Long KR, Van Gosen BS, Foley NK, Cordier D (2010) The principal rare earth elements deposits of the United States – a summary of domestic deposits and a global perspective. US Geol Surv scientific investigations report 2010–5220. US Geol Surv, Reston, 96 pp

  • Matthews WK III, Adams JAS (1986) Geochemistry, age, and structure of the Sierra Blanca and Finlay Mountain intrusions, Hudspeth County, Texas. Bureau of Economic Geology, University of Texas at Austin. Guidebook no 23, pp 207–224

  • McAnulty WN (1980) Geology and mineralization of the Sierra Blanca peaks, Hudspeth County, Texas. New Mexico Geol Soc, Socorro. Guidebook no 31, pp 263–266

  • Muehlberger WR (1980) Texas Lineament revisited. New Mexico Geol Soc, Socorro. Guidebook no 31, pp 113–121

  • Muller A, Seltman R, Kober B, Eklund O, Jeffries T, Kronz A (2008) Compositional zoning of rapakivi feldspars and coexisting quartz phenocrysts. Can Mineral 46:1417–1442

    Article  Google Scholar 

  • Muller A, van der Kerkhof AM, Behr HJ, Kronz A, Koch-Muller M (2009) The evolution of late-Hercynian granites and rhyolites documented by quartz – a review. Earth Env Sci ´T R So 100(1–2):185–204

    Google Scholar 

  • Nesse WD (2000) Introduction to mineralogy. Oxford University Press, New York, 442 pp

    Google Scholar 

  • O’Neill LC (2014) REE-Be-U-F mineralization of the Round Top laccolith, Sierra Blanca peaks, Trans-Pecos Texas. MSc thesis, University of Texas at Austin

  • Pingitore N, Clague J, Gorski D (2014) Round Top Mountain rhyolite (Texas, USA), a massive, unique Y bearing-fluorite-hosted heavy rare earth element (HREE) deposit. J Rare Earths 32(1):90–96

    Article  Google Scholar 

  • Price JG, Henry CD, Barker DS, Parker DF (1987) Alkalic rocks of contrasting tectonic settings in Trans-Pecos Texas. In: Mullen Morris E, Pasteris JD (eds) Mantle metasomatism and alkaline magmatism, Geol Soc Am Spec Pap, vol 215. Boulder, Geological Soc Am, pp 335–346

    Chapter  Google Scholar 

  • Price JG, Rubin JN, Henry CD, Pinkston TL, Tweedy SW, Koppenaal DW (1990) Rare-metal enriched peraluminous rhyolites in a continental arc, Sierra Blanca area, Trans-Pecos Texas; chemical modification by vapor-phase crystallization. In: Stein HJ, Hannah JL (eds) Ore-bearing granite systems; Petrogenesis and mineralizing processes, Geol Soc Am Spec Pap, vol 215. Boulder, Geological Soc Am, pp 335–346

    Google Scholar 

  • Rubin JN, Price JG, Henry CD, Koppenaal DW (1987) Cryolite-bearing and rare metal-enriched rhyolite, Sierra Blanca peaks, Hudspeth County, Texas. Am Mineral 72(11–12):1122–1130

    Google Scholar 

  • Rubin JN, Henry CD, Price JG (1989a) Hydrothermal zircons and zircon overgrowths, Sierra Blanca peaks. Texas: Am Mineral 74(7–8):865–869

    Google Scholar 

  • Rubin JN, Price JG, Henry CD, Pinkston TL, Tweedy SW, Koppenaal DW, Peterson SB, Harlan HM, Miller WT, Thompson RJ, Grabowski RB, Laybourn PD, Schrock GE, Johnson A, Staes DG, Gaines RV, Miller FH (1989b) Mineralogy of beryllium deposits near Sierra Blanca, Texas. Proc Metal 5:601–614

    Google Scholar 

  • Rubin JN, Price JG, Henry CD, Kyle JR (1990) Geology of the beryllium-rare earth element deposits at Sierra Blanca, West Texas. In: Kyle JR (ed) Industrial mineral ressources of the Delaware Basin, Texas and New Mexico. Guidebook series, vol 8. Littleton, Soc Econ Geol, pp 191–203

    Google Scholar 

  • Rubin JN, Henry CD, Pinkston TL, Tweedy SW, Koppenaal DW (1993) The mobility of zirconium and other 'immobile' elements during hydrothermal alteration. Chem Geol 110(1–3):29–47

    Article  Google Scholar 

  • Shannon WM (1986) Lithogeochemical characterization of intrusive rocks comprising the Quitman-Sierra Blanca igneous complex, Hudspeth County, Texas. MSc thesis, University of Texas at El Paso

  • Shannon WM, Goodell PC (1986) Lithogeochemistry of intrusive rocks of the Quitman-Sierra Blanca igneous complex, Hudspeth County, Texas. Bureau of Economic Geology, University of Texas at Austin, Guidebook no 23, pp 225–236

  • Shelley D (1992) Igneous and metamorphic rocks under the microscope: classification, textures, microstructures and mineral preferred-orientations. Chapman & Hall London, 450 pp

  • Vernon RH (2004) A practical guide to rock microstructure. Cambridge University Press, Cambridge, 606 pp

    Book  Google Scholar 

  • Wilson JA (1980) Geochronology of the Trans-Pecos Texas volcanic field. New Mexico Geol Soc, Socorro. Guidebook no 31:205–211

    Google Scholar 

  • Zachariansen WH (1951) Crystal chemical studies of the 5f-series of elements. XIV. Oxyfluorides, XOF. Acta Crystallogr 4:231–236

    Article  Google Scholar 

Download references

Acknowledgements

We thank the Texas Rare Earth Resources Corporation for permission to conduct research on their property, assistance in conducting fieldwork, and providing access to existing maps, drill-hole data and samples, and previous studies. We are indebted to two anonymous experts as well as editor Daniel Harlov whose critical and constructive reviews helped to greatly improve the manuscript’s overall content and quality. The funding for this study was provided by the Jackson School of Geosciences and the State of Texas Advanced Resource Recovery (STARR) program through the University of Texas at Austin, Bureau of Economic Geology, Mineral Resource Program. This study was greatly enhanced by regional mapping products, produced by the University of Texas at Austin Bureau of Economic Geology, and funded through the United States Geological Survey Mapping Cooperative Program, STATEMAP Award No. G13AC00178. Additional support for O’Neill (2014) thesis research was provided by the III Yager Professorship of the Jackson School of Geosciences, the West Texas Geological Society, the Society of Economic Geologists, and the Association of Environmental and Engineering Geologists.

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Authors and Affiliations

  1. Department of Geological Sciences, University of Texas, Austin, TX, 78712, USA

    L. Christine O’Neill & J. Richard Kyle

  2. Bureau of Economic Geology, University of Texas, University Station, Box X, Austin, TX, 78713-8924, USA

    Brent A. Elliott & J. Richard Kyle

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  1. L. Christine O’Neill
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  2. Brent A. Elliott
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Correspondence to Brent A. Elliott.

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Editorial handling: D. Harlov

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O’Neill, L.C., Elliott, B.A. & Kyle, J.R. Mineralogy and crystallization history of a highly differentiated REE-enriched hypabyssal rhyolite: Round Top laccolith, Trans-Pecos, Texas. Miner Petrol 111, 569–592 (2017). https://doi.org/10.1007/s00710-017-0511-5

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