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On synneusis

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Abstract

Synneusis is the process of drifting-together and mutual attachment of crystals suspended in a melt. This process is episodic, is most characteristic of the earlier stages of consolidation, and appears to be related to magmatic turbulence. Union of crystals in synneusis relation normally occurs on their broader faces in preferred orientations which coincide with positions of low interfacial energy. Quantitative studies of several common igneous minerals indicate that crystals of a single mineral characteristically show a strong affinity for synneusis and typically unite in parallel or twinned orientation. Some pairs of unlike minerals join readily in synneusis relation, but most appear to be antipathetic.

Synneusis structures have generally been overlooked or misinterpreted as epitaxial intergrowths, primary twins, irregular growth forms, or the random union of crystals which have grown into contact. These possibilities must be rejected where it can be shown that two or more distinct crystals are involved, that they were relatively large when they came in contact, and that they are oriented with prominent faces in common.

Synneusis is responsible for three major features of the magmatic fabric: (1) the small scale segregation of minerals; (2) the systematic mutual orientation of adjacent crystals in synneusis relation; and (3) the morphology of their common boundary. Because synneusis structures are restricted to igneous rocks and are widespread and easily recognized, they provide a definitive and ready criterion of magmatic origin.

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References

  • Balogh, E.: Allgemeines Vorkommen von nicht parallelachsigen Zwillingen unter den Quarzporphyren. “Múzeumi Füzetek”, Kolozsavar 2, 242 (1913).

    Google Scholar 

  • Brothers, R. N.: Petrofabric analyses of Rhum and Skaergaard layered rocks. J. Petrol. 5, 255–274 (1964).

    Google Scholar 

  • Brown, G. M.: The layered ultrabasic rocks of Rhum, Inner Hebrides. Phil. Trans. Roy. Soc. (Lond.), Ser. B 240, 1–53 (1956).

    Article  Google Scholar 

  • Buerger, M. J.: The genesis of twin crystals. Am. Mineralogist 30, 469–482 (1945).

    Google Scholar 

  • Burri, C.: Bemerkungen zur sog. “Banater Verwachsung” der Plagioklase. Schweiz. Mineral. Petrog. Mitt. 43, 72–80 (1963).

    Google Scholar 

  • Cannon, R. T.: Porphyroblastic and augen gneisses in the Bartica assemblage, British Guiana. Geol. Mag. 101, 541–547 (1964).

    Article  Google Scholar 

  • Chudoba, K. F., u. L. Frechen: Die frühmagmatische Bildung der Olivinausscheidungen von Finkenberg (Siebengebirge) und Dreiser Weiher (Eifel), Geol. Rundschau 32, 256–278 (1941).

    Article  Google Scholar 

  • Drugman, J.: β-quartz twins from Cornwall. Mineral. Mag. 21, 336–382 (1928).

    Google Scholar 

  • —: On some unusual twin-laws observed in the orthoclase crystals from Goodsprings Nevada: Mineral. Mag. 25, 1–14 (1938).

    Article  Google Scholar 

  • Frasl, G.: Anzeichen schmelzflüssigen und hochtemperierten Wachstums an den großen Kalifeldspaten einiger Prophyrgranite, Porphyrgranitgneise und Augengneise Österreichs. Jahrb. Geol. Bundesanstalt 97, 71–131 (1954).

    Google Scholar 

  • Frondel, C.: Oriented inclusions of staurolite, zircon, and garnet in muscovite. Skating crystals and their significance. Am. Mineralogist 25, 69–87 (1940).

    Google Scholar 

  • —: Dana's System of mineralogy, vol. III. Silica minerals, 7th ed. New York: John Wiley & Sons 1962.

    Google Scholar 

  • Gaubert, P.: Sur la production artificielle de la macle des spinelles dans les cristaux d'azotate de plomb. Bull. Soc. Franc. Mineral. 19, 431–434 (1896).

    Google Scholar 

  • Gorai, M.: Petrological studies on plagioclase twins. Am. Mineralogist 36, 884–901 (1951).

    Google Scholar 

  • Harker, A.: Petrology for students, 8th edit., revised. London: Cambridge University Press 1964.

    Google Scholar 

  • Hartman, P.: On the morphology of growth twins. Z. Krist. 107, 225–237 (1956).

    Article  Google Scholar 

  • Hibbard, M. J.: Origin of some alkali feldspar phenocrysts and their bearing on petrogenesis. Am. J. Sci. 263, 245–261 (1965).

    Article  Google Scholar 

  • Ingerson, E.: Twinning frequency in feldspar phenocrysts from a quartz latite sill at Sierra Blanca, Texas. Am. J. Sci., Bowen volume, 189–202 (1952).

  • Köhler, A., u. F. Raaz: Gedanken über die Bildung von Feldspat-Zwillingen in Gesteinen. Verhandl. Geol. Bundesanstalt, (Jg. 1945), 163–171 (1947).

  • Kraus, G.: Gefüge, Kristallgrößen und Genese des Kristallgranites I im vorderen Bayerischen Wald. Neues Jahrb. Mineral. 97, 357–434 (1962).

    Google Scholar 

  • —: Das Apatit-Zirkongefüge in den Wirtmineralen Hornblende und Biotit effusiver und “granitischer” Gesteine. Mineral. Petrog. Mitt. 8, 335–360 (1963).

    Article  Google Scholar 

  • Laemmlein, G.: Korrosion und Regeneration der Porphyr-Quarze. Z. Krist. 75, 109–127 (1930).

    Google Scholar 

  • - On regular intergrowths of porphyry-quartz on the (10¯11) face. Trav. Lab. Crist. Acad. Sci. URSS, No. 2, 123–148 (M. A. 9–211) (1940).

  • Larsen, L., and A. Poldervaart: Measurement and distribution of zircons in some granitic rocks of magmatic origin. Mineral. Mag. 31, 554–564 (1957).

    Article  Google Scholar 

  • Maucher, A.: Über geregelte Plagioklaseinschlüsse in Orthoklas und Sanidin. Z. Krist. 105, 82–90 (1943).

    Google Scholar 

  • McMahon, C. A.: On the polysynthetic structure of some porphyritic quartz crystals in quartz-felsite. Mineral. Mag. 8, 10–14 (1888).

    Article  Google Scholar 

  • Moorhouse, W. W.: The paragenesis of accessory minerals. Econ. Geol. 51, 248–262 (1956).

    Article  Google Scholar 

  • —: The study of rocks in thin section. New York: Harper & Brothers 1956.

    Google Scholar 

  • Ross, J. V.: Combination twinning in plagioclase feldspars. Am. J. Sci. 255, 650–655 (1957).

    Article  Google Scholar 

  • Schaskolsky, M., u. A. Schubnikow: Über die künstliche Herstellung gesetzmäßiger Kristallverwachsungen des Kalialauns. Z. Krist. 85, 1–16 (1933).

    Google Scholar 

  • Schermerhorn, L. J. G.: The paragenesis of accessory minerals in igneous rocks. Econ. Geol. 53, 215–218 (1958).

    Article  Google Scholar 

  • Seifert, K. E.: The genesis of plagioclase twinning in the Nonewaug granite. Am. Mineralogist 49, 297–320 (1964).

    Google Scholar 

  • Smithson, S. B.: Oriented plagioclase grains in K-feldspar porphyroblasts. Contrib. Geol. Univ. Wyoming, 4, 63–68 (1965).

    Google Scholar 

  • Tertsch, H.: Beobachtungen an Orthoklas-Zwillingen nach dem Karlsbader Gesetz. Zentr. Mineral. Geol. Paläont., Abt. A, 198–207 (1936).

  • Turner, F. J.: Observations on twinning of plagioclase in metamorphic rocks. Am. Mineralogist 36, 581–589 (1951).

    Google Scholar 

  • Tuttle, O. F., and N. L. Bowen: Origin of granite in the light of experimental studies in the system NaAlSi3O8-KAlSi3O8-SiO2-H2O. Geol. Soc. Am. Mem. 74 (1958).

  • Vance, J. A.: Polysynthetic twinning in plagioclase. Am. Mineralogist 46, 1097–1119 (1961).

    Google Scholar 

  • —, and J. P. Gilreath: The effect of synneusis on phenocryst distribution patterns in some porphyritic igneous rocks. Am. Mineralogist 52, 529–536 (1967).

    Google Scholar 

  • Viola, C.: Beitrag zur Zwillingsbildung: Z. Krist. 36, 234–244 (1902).

    Google Scholar 

  • Vogel, T. A.: Optical-crystallographic scatter in plagioclase. Am. Mineralogist 49, 614–633 (1964).

    Google Scholar 

  • Vogt, J. H. L.: The physical chemistry of the crystallization and magmatic differentiation of the igneous rocks. J. Geol. 29, 318–350 (1964).

    Article  Google Scholar 

  • Williams, H., F. J. Turner, and C. M. Gilbert: Petrography. San Francisco: W. H. Freeman 1955.

    Google Scholar 

Download references

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  1. Department of Geological Sciences, University of Washington, 98105, Seattle, Washington

    Joseph A. Vance

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  1. Joseph A. Vance
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Vance, J.A. On synneusis. Contr. Mineral. and Petrol. 24, 7–29 (1969). https://doi.org/10.1007/BF00398750

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