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Rare earth abundances and origin of some Indian lamprophyres

Published online by Cambridge University Press:  01 May 2009

D. K. Paul  and
P. J. Potts
D. K. Paul
Affiliation:
Geochronology Division, Geological Survey of India, Calcutta, India
P. J. Potts
Affiliation:
Department of Earth Sciences, The Open University, Milton Keynes, England
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Summary

Abundances of rare-earth elements (REE) and Th, Ta, Hf, Sc, Co, Ba determined by instrumental neutron activation analysis show similarity between lamprophyres and other potassic rocks including kimberlite. The Indian lamprophyres have fractionated REE patterns with enrichment of light REE. The light REEs show more variation than the heavy REEs within the group.

Lamprophyres occurring in intimate association with the alkaline basalt may be genetically related. The trace element characteristics of the abundant lamprophyre dykes in granitic terrain are unlikely to be generated by assimilation of alkaline basalt by granitic crust. Small amounts of partial melting in mantle pockets enriched in incompatible elements as a result of metasomatic processes would explain the elemental concentration observed in the lamprophyres.

Type
Articles
Information
Geological Magazine , Volume 118 , Issue 4 , July 1981 , pp. 393 - 399
Copyright
Copyright © Cambridge University Press 1981

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References

Bachinski, S. W. & Scott, R. B. 1979. Rare earth and other trace element contents and the origin of minettes (mica – lamprophyres) Geochim. cosmochim. Acta 43, 93–100.CrossRefGoogle Scholar
Bose, M. K. 1973. Petrology and geochemistry of the igneous complex of Mount Girnar, Gujarat, India Contr. Mineral. Petrol. 39, 247–66.CrossRefGoogle Scholar
Carmichael, I. S. E., Turner, F. & Vernoogen, J. 1974. Igneous Petrology. 508–510. New York: McGraw-Hill.Google Scholar
Eby, G. N. 1975. Abundance and distribution of the rare earth elements and yttrium in the rocks and minerals of the Oka carbonatite complex, Quebec Geochim. cosmochim. Acta 39, 597–620.CrossRefGoogle Scholar
Herrmann, A. G. 1970. Yttrium and lanthanides. In Handbook of Geochemistry, vol. II/2 (ed. Wedepohl, K. H.). Springer.Google Scholar
Hutchison, R., Chambers, A. L., Paul, D. K. & Harris, P. G. 1975. Chemical variation among French ultramafic xenoliths – evidence for a heterogeneous upper mantle Mineral. Mag. 40, 153–70.CrossRefGoogle Scholar
Kay, R. W. & Gast, P. W. 1973. The rare earth content and the origin of alkali rich basalts J. Geol. 81, 653–82.CrossRefGoogle Scholar
Kurat, G., Palme, H., Spettel, B., Baddenhausen, H., Hofmeister, H., Palme, C. & Wanke, H. 1980. Geochemistry of ultramafic xenoliths from Kapfenstein, Austria: evidence for a variety of upper mantle processes Geochim. cosmochim. Acta 44, 45–60.CrossRefGoogle Scholar
Mitchell, R. H. & Brunfelt, A. O. 1975. Rare earth geochemistry of kimberlite. Physics Chem. Earth, 9, 671–86.CrossRefGoogle Scholar
Nakamura, N. 1974. Determination of REE, Ba, Fe, Mg, Na and K in carbonaceous and ordinary chondrite Geochim. cosmochim. Acta 38, 757–76.CrossRefGoogle Scholar
Paul, D. K., Potts, P. J., Gibson, I. L. & Harris, P. G. 1975. Rare earth abundance in Indian kimberlite Earth Planet. Sci. Lett. 25, 151–8.CrossRefGoogle Scholar
Reitan, P. H. 1974. Eu anomaly in kimberlites. Geology 2, 72.2.0.CO;2>CrossRefGoogle Scholar
Rock, N. M. S. 1977. The nature and origin of lamprophyres, some definitions, distinctions and derivations Earth Sci. Rev. 13, 123–69.CrossRefGoogle Scholar
Sarkar, A., Paul, D. K., Balasubrahmanyan, M. N. & Sengupta, N. R. 1980. Lamprophyres from Indian Gondwanas - K-Ar ages and chemistry J. geol. Soc. India 21, 188–93.Google Scholar
Scott, B. H. 1979. Petrogenesis of kimberlites and associated potassic lamprophyres from central West Greenland. Kimberlites, diatremes and diamonds – their geology, petrology and geochemistry Proc. 2nd Int. Kimberlite Conf. 1, 190–205.Google Scholar
Steele, K. & Wagner, G. H. 1979. Relationship of the Murfreesboro kimberlite and other igneous rock of Arkansas, U.S.A Proc. 2nd Int. Kimberlite Conf. 1, 393–4.Google Scholar