Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-15T03:23:22.969Z Has data issue: false hasContentIssue false

Mineralogy and petrology of some Tertiary leucite-rhönite basanites from central France

Published online by Cambridge University Press:  05 July 2018

M. C. Magonthier
Affiliation:
Laboratoire de Pétrographie, Université de Paris VI, 4 place Jussieu, 75230-PARIS Cedex 05, France
D. Velde
Affiliation:
Laboratoire de Pétrographie, Université de Paris VI, 4 place Jussieu, 75230-PARIS Cedex 05, France

Summary

The composition of the various phases present in the rh6nite-bearing leucite basanites of the southern part of the Sillon Houiller district have been determined with the electron microprobe. Clinopyroxenes show strong progressive enrichment in Al2O3 and TiO2, maximum values being 13 % and 6 % respectively. These extreme compositions are comparable to others found in feldspathoidal lavas from other provinces, and can be explained by the low silica content of the liquids they crystallized from, and high cooling-rates. Rhönite composition is similar to those previously determined in various terrestrial occurrences. The chemical compositions of the lavas differ from those of basanites, and are intermediate as far as Ca, Al, and Si contents between basanites and melilite-bearing basic lavas. The presence of rhönite can be explained by bulk composition, but is not a consequence of a particularly high Fe and/or Ti content. Xenoliths are absent from these lavas, so that there is no petrographic indication of possible contamination. It is tentatively concluded that the high K/Na ratio is primary.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1976

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Akella, (J.) and Boyd, (F. R.), 1972. Carnegie Inst. Wash. Year Book, 71, 378-84.Google Scholar
Best, (G. M.), 1974. Journ. Geophys. Res. 79, 2107-13.CrossRefGoogle Scholar
Best, (G. M.), and Brimnall, (W. H.), 1974. Geol. Soc. America Bull. 85, 1677-90.2.0.CO;2>CrossRefGoogle Scholar
Biggar, (G. M.), O'Hara, (M. J.), Peckett, (A.), and Humpnries, (D. J.), 1971. Proe. 2nd Lunar Sci. Conf., Suppl. 2, vol. I, Geoehimiea Acta, 617-43.Google Scholar
Brousse, (R.), 1961. Bull. Serv. Carte Gdol. France, 263, 58. 1-140.Google Scholar
Brousse, (R.), 1971. Clermont Ferrand, Ed. Plein Air Serv. 377-478.Google Scholar
Cameron, (K. L.), Carman, (M. F.), and Butler, (J. C.), 1970. Amer. Min. 55, 864-74.Google Scholar
Cogné, (J.), Geze, (B.), and Goguel, (J.), 1966. Rev. Geogr. Phys. Géol. Dyn. 8, 123-31.Google Scholar
Conquéré, (F.), 1971a. Contr. Min. Petr. 30, 291-5.CrossRefGoogle Scholar
Conquéré, (F.), 1971b. Ibid. 33, 32-61.Google Scholar
Ficke, (B.), 1961. Tschermaks Min. Petr. Mitt. 7, 337-436.CrossRefGoogle Scholar
Fuchs, (L. H.), 1971. Amer. Min. 56, 2053-68.Google Scholar
Gramse, (M.), 1970. Contr. Min. Petr. 29, 43-73.CrossRefGoogle Scholar
Grolier, (J.) and Letourneur, (J.), 1968. 23rd Int. Geol. Congr. Rep. 1, 107-16.Google Scholar
Grunhagen, (H.) and Seck, (H. A.), 1972. Tschermaks Min. Petr. Mitt. 18, 17-38.CrossRefGoogle Scholar
Gupta, (A. K.), Onuma, (K.), Yagi, (K.), and Lidiak, (E. G.), 1973. Contr. Min. Petr. 41, 333-44.CrossRefGoogle Scholar
Hamm, (H. M.) and Vieten, (K.), 1971. Neues Jahrb. Min., Monatsh., 310-14.Google Scholar
Hernandez, (J.), 1973. Bull. Soe. franG Min. Crist. 96, 303-12.Google Scholar
Huckenholz, (H. G.), Lindhuber, (W.), and Springer, (J.), 1974. Neues Jahrb. Min., Abh. 121, 160-207.Google Scholar
Kyle, (P. R.) and Price, (R. C.), 1975. Amer. Min. 60, 722-25.Google Scholar
Lacroix, (A.), 1917. Compt. Rend. Acad. Sci. Paris, 165, 381-87.Google Scholar
Lacroix, (A.), 1923. Mindralogie de Madagascar, 3, Paris, Challamel Ed. Google Scholar
Lofgren, (G.), Donaldson, (C. H.), Williams, (R. J.), Mullins, (O. Jr.), and Usselman, (T. M.), 1974. Proc. 5th Lunar Sci. Conf., Suppl. 5, vol. I, Geochimica Acta, 549-67.Google Scholar
Lowder, (G. G.), 1973. Geol. Soc. America Bull. 84, 2993-3012.2.0.CO;2>CrossRefGoogle Scholar
Mackenzie, (W. S.) and Rahman, (S.), 1968. Contr. Min. Petr. 19, 339-42.CrossRefGoogle Scholar
Magonthier, (M. C.), 1974. Thèse de 3ème cycle, Paris. Google Scholar
Magonthier, (M. C.), 1975. Bull. Soc. frang. Min. Crist. Google Scholar
Morawski, (A.), Bence, (A. E.), and Papike, (J. J.), 1975. EOS Trans. Amer. Geophys. Union, 56, 468 (abstract).Google Scholar
O'Hara, (M. J.) and Schairer, (J. F.), 1963. Carnegie Inst. Wash. Year Book, 62, 107-15.Google Scholar
Rucklidge, (J.) and Gasparrini, (E. L.), 1969. Electron microprobe analytical reduction EMPADR VII, University of Toronto, Dept. of Geology.Google Scholar
Shrbeny, (O.) and Machacek, (V.), 1974. Časopis Mineral geol. 19, 15-25.Google Scholar
Stormer, (J. C.), 1972. Geol. Soc. America Bull. 83, 3299-322.CrossRefGoogle Scholar
Tournon, (J.) and Velde, (D.), 1971. Contr. Min. Petr. 30, 291-5.CrossRefGoogle Scholar
Tracy, (R. J.) and Robinson, (P.), 1975. EOS Trans. Amer. Geophys. Union, 56, 465 (abstract).Google Scholar
Velde, (D.), 1973. Compt. Rend. Acad. Sci. Paris, 276, 3257-60.Google Scholar
Velde, (D.), and Thiébaut, (J.), 1973. Bull. Soc. franG Min. Crist. 96, 298-302.Google Scholar
Velde, (D.), and Frain, De La Gaulayrie (P. S.), 1974. Ibid. 97, 450-64.CrossRefGoogle Scholar