Skip to main content
SpringerLink
Log in

An analytical electron microscopic study of a pyroxene-amphibole intergrowth

  • Published:
Contributions to Mineralogy and Petrology Aims and scope Submit manuscript

Abstract

Samples of a garnet granulite from the mafic border units of the Lake Chatuge, Georgia alpine peridotite body were found to contain lamellar intergrowths of a pargastic amphibole in augite having the typical appearance of an exsolution feature. Single crystal X-ray diffraction, optical, electron microprobe and conventional and analytical electron microscopic studies have provided data limiting the compositions and structures of the coexisting phases. Individual lamellae of both materials are from 0.5 to 2.0 μm in width with the lamellar interface parallel to {0 1 0}. The formulae of the minerals, as determined by a combination of electron microprobe and analytical electron microscopy, are (Na0.1Ca1.0Mg0.6Fe3+ 0.3)(Si1.8Al0.2)O6 for the pyroxene and Na0.7Ca1.9(Mg2.1Fe2+ 1.4Fe3+ 0.5Ti0.1Cr0.1Al0.8)(Si5.9Al2.1) O22(OH)2 for the amphibole. Several other studies have described intergrowths similar to those observed in this work, in general favoring exsolution as the formation mechanism for the intergrowths. In the Lake Chatuge samples however, replacement of pyroxene by amphibole is in part indicated by continuous gradation of amphibole lamellae into amphiboles rimming the clinopyroxenes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Blake DF, Allard LF, Peacor DR, Bigelow WC (1980) “Ultra-clean” X-ray spectra in the JEOL JEM-100CX. Proc 38th Ann Mtg Electron Microsc Soc Am, pp 136–137

  • Cliff G, Lorimer GW (1972) The quantitative analysis of thin metal foils using EMMA-4 — the ratio technique, Proc 5th Eur Congr Electron Microsc. Inst Physics, London, pp 140–141

    Google Scholar 

  • Chliff G, Lorimer GW (1975) The quantitative analysis of thin specimens. J Microsc 103:203–207

    Google Scholar 

  • Dallmeyer RD (1974) Eclogite inclusions in an alpine peridotite sill, Georgia-North Carolina: their chemistry and petrogenetic evolution. Am J Sci 274:356–377

    Google Scholar 

  • Desnoyers C (1975) Exsolution d'amphibole, de grenat et de spinelle dans les pyroxènes de roches ultrabasiques: péridotite et pyroxénolites. Bull Soc Fr Mineral Crystallogr 98:65–77

    Google Scholar 

  • Goldstein JJ, Costley JL, Lorimer GW, Reed SJB (1977) Quantitative X-ray analysis in the electron microscope. Proc Workshop Analyt Electron Microsc 1. Chicago, SEM, pp 315–323

    Google Scholar 

  • Hartley ME III (1973) Ultramafic and related rocks in the vicinity of Lake Chatuge. Ga Dept Nat Res Bull 85:1–61

    Google Scholar 

  • Lorimer GW, Champness PE (1973) Combined electron microscopy and analysis of an orthopyroxene. Am Mineral 58:243–248

    Google Scholar 

  • Lorimer GW, Cliff G, Clark JN (1976) Determination of the thickness and spatial resolution for the quantitative analysis of thin foils. In: Developments in Electron Microscopy and Analysis. Proc Electron Microsc Analyt Group 75. Academic, Bristol London, pp 153–156

    Google Scholar 

  • Nakajima Y, Hafner SS (1980) Exsolution in augite from the Skaergaard intrusion. Contrib Mineral Petrol 72:101–110

    Google Scholar 

  • Nakajima Y, Ribbe PH (1980) Alteration of pyroxenes from Hokkaido, Japan to amphiboles, clays, and other biopyriboles. Neues Jahrb Mineral 6:258–268

    Google Scholar 

  • Papike JJ, Ross M, Clark JR (1969) Crystal chemical characterization of amphiboles based on five new structure determinations. Mineral Soc Am, Spec Pap 2:117–136

    Google Scholar 

  • Rucklidge JC, Gasparrini EL (1969) Specifications of a complete program for processing electron microprobe data: EMPADR VII. Dept Geol, Univ Toronto

  • Smith PPK (1977) An electron microscopic study of amphibole lamellae in augite. Contrib Mineral Petrol 59:317–322

    Google Scholar 

  • Veblen DR, Buseck PR (1977) Petrologic implications of hydrous biopyriboles intergrown with igneous pyroxene. Trans Am Geophys Union (EOS) 58:1242

    Google Scholar 

  • Veblen DR, Busek PR (1980) Microstructures and reaction mechanisms in biopyriboles. Am Mineral 65:599–623

    Google Scholar 

  • Ymaguchi Y, Akai J, Tomity K (1978) Clinoamphibole lamellae in diopside of garnet lherzolite from Alpe Arami, Bellinzona, Switzerland. Contrib Mineral Petrol 66:263–270

    Google Scholar 

Download references

Author information

Author notes

  1. Philip E. Brown

    Present address: Department of Geology and Geophysics, The University of Wisconsin, 53706, Madison, WI, USA

  2. John W. Valley

    Present address: Department of Geology, Rice University, P.O.Box 1892, 77001, Houston, TX, USA

Authors and Affiliations

  1. Department of Geological Sciences, The University of Michigan, 48109, Ann Arbor, Michigan, USA

    Andrew M. Isaacs, Philip E. Brown, John W. Valley, Eric J. Essene & Donald R. Peacor

Authors
  1. Andrew M. Isaacs
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Philip E. Brown
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. John W. Valley
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Eric J. Essene
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Donald R. Peacor
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

Contribution No. 368 from the Mineralogical Laboratory, Department of Geological Sciences, The University of Michigan, Ann Arbor, Michigan

Rights and permissions

Reprints and permissions

About this article

Cite this article

Isaacs, A.M., Brown, P.E., Valley, J.W. et al. An analytical electron microscopic study of a pyroxene-amphibole intergrowth. Contr. Mineral. and Petrol. 77, 115–120 (1981). https://doi.org/10.1007/BF00636515

Download citation

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00636515

Keywords

Search

Navigation