Abstract
Samples obtained by U.S. Department of Energy research drilling at the 600-year-old Obsidian Dome volcano provide the rare opportunity to examine the transition from volcanic (dome) to plutonic (intrusion) textures in a silicic magma system. Textures in the lavas from Obsidian Dome record multiple periods of crystallization initiated in response to changes in undercooling (ΔT) related to variable degassing in the mag-ma. Phenocr)ysts formed first at low ΔT. A drastic increase in ΔT, related to loss of a vapor phase during initial stages of eruption, caused nucleation of microlites. All of the lavas thus contain phenocrysts and microlites. Extrusion and subsequent devitrification of the dry (0.1 wt% H2O) magma crystallized spherulites and fine-grained rhyolite at high ΔT. A granophyric texture, representing crystallization at a moderate ΔT, formed in the intrusions beneath Obsidian Dome. Textures in the intrusion apparently represent crystallization of hydrous (1–2 wt% H2O) rhyolitic magma at shallow depths.
Similar content being viewed by others
References
Akizuki M (1983) An electron microscope study of anorthoclase spherulites. Lithos 16:249–254
Burnham CW (1979) Magmas and hydrothermal fluids. In: Barnes HL (ed) Geochemistry of hydrothermal ore deposits, 2nd ed. Wiley, New York, pp 71–136
Cashman KV, Marsh BD (1984) Crystal-size spectra and kinetics of crystal growth in magma: II. Application. Geol Soc Am Abstr Progr 16:345
Cashman KV, Marsh BD (1986) Crystal size distributions (CSDs) and crystallization of Mt St Helens 1980–1986 dacite. Geol Soc Am Abstr Progr 18:559
Dowty E (1980) Crystal growth and nucleation theory and the numerical simulation of igneous crystallization. In Hargraves RB (ed) The physics of magmatic processes. Princeton University Press, Princeton, pp 419–485
Eichelberger JC, Westrich HR (1981) Magmatic volatiles in explosive rhyolitic eruptions. Geophys Res Let 8:757–760
Eichelberger JC, Lysne PC, Younker LW (1984) Research drilling at Inyo Domes, Long Valley Caldera, California. EOS, Trans Am Geophys Union 65:721–725
Eichelberger JC, Lysne PC, Miller CD, Younker LW (1985) Research drilling at Inyo Domes, California: 1984 results. EOS Trans Am Geophys Union 66:186–187
Eichelberger JC, Carrigan CR, Westrich HR, Price RH (1986) Non-explosive silicic volcanism. Nature 323:598–602
Fenn PM (1977) The nucleation and growth of alkali feldspars from hydrous melts. Can Mineral 15:135–161
Keith HD, Padden FJ Jr (1963) A phenomenological theory of spherulitic crystallization. J Appl Phys 34:2409–2421
Kirkpatrick RJ (1977) Nucleation and growth of plagioclase, Makaopuhi and Alae lava lakes, Kilauea Volcano, Hawaii. Geol Soc Am Bull 88:78–84
Lofgren GE (1971) Experimentally produced devitrification textures in natural rhyolitic glass. Geol Soc Am Bull 82:111–124
Lofgren GE (1974) An experimental study of plagioclase crystal morphology: Isothermal crystallization, Am J Sci 274:243–273
Lofgren GE (1983) Effect of heterogeneous nucleation on basaltic textures: a dynamic crystallization study. J Petrol 24:229–255
Luth WC, Jahns RH, Tuttle OF (1964) The granite system at pressures of 4 to 10 kilobars. J Geophys Res 69:759–773
Miller CD (1985) Holocene eruptions at the Inyo volcanic chain, California: Implications for possible eruptions in Long Valley Caldera. Geology 13:14–17
Naney MT (1983) Phase equilibria of rock-forming ferromagnesian silicates in granitic systems. Am J Sci 283:993–1033
Naney MT, Swanson SE (1980) The effect of Fe and Mg on crystallization in granitic systems. Am Mineral 65:639–653
Peck DL, Wright TL, Moore JG (1966) Crystallization of tholeiitic basalt in Alae lava lake, Hawaii. Bull Volcanol 29:629–656
Sampson DE, Cameron KL (1987) The geochemisty of the Inyo volcanic chain: multiple magma systems in the Long Valley Region, eastern California. J Geophys Res 92:10403–10421
Shaw HR (1974) Diffusion of H2O in granitic liquids. Part I. Experimental data; Part II. Mass transfer in magma chambers. In: Hoffman AW, Gileti BJ, Yokder HS Jr, Yund RA (eds) Geochemical transport and kinetics. Carnegie Inst Wash Publ 643:139–170
Smith RL (1960) Zones and zonal variations in welded ash flows. US Geol Surv Prof Pap 354-F: 1–159
Swanson SE (1977) Relation of nucleation and crystal-growth rate to the development of granitic textures. Am Mineral 62:966–978
Tuttle OF, Bowen NL (1958) The origin of granite in light of experimental studies in the system NaAlSi3O8—KAlSiO2 —H2O. Geol Soc Am Mem 74:1–153
Vogel TA, Younker LW, Schuraytz BC (1987) Constraints on magma ascent, emplacement, and eruption: Geochemical and mineralogical data from drill-core samples at Obsidian Dome, Inyo chain, California. Geology 15:405–408
Whitney JA (1975) The effects of pressure, temperature, and XH2O on phase assemblage in four synthetic rock compositions. JGeol 83:1–31
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Swanson, S.E., Naney, M.T., Westrich, H.R. et al. Crystallization history of Obsidian Dome, Inyo Domes, California. Bull Volcanol 51, 161–176 (1989). https://doi.org/10.1007/BF01067953
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01067953