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Origin of fine-grained granular rocks in layered intrusions

Published online by Cambridge University Press:  01 May 2009

P. Thy  and
K. H. Esbensen
P. Thy
Affiliation:
Nordic Volcanological Institute University of Iceland 101 Reykjavik Iceland
K. H. Esbensen
Affiliation:
Department of Metallurgy Technical University of Denmark Building 204 2800 Lyngby Denmark
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Summary

Extremely fine-grained granular rocks are found interleaved with cumulates in some layered differentiated intrusions. The question arises as to whether these can be interpreted as chilled magmas. If this were so it would allow the liquid line of descent to be determined directly. A study of extremely fine-grained granular rocks in the differentiated, layered basic Fongen–Hyllingen complex, Norway, however, showed rocks of this type to be cumulates. Fluctuations in volatile pressure due to crystallization of a hydrous phase may give rise to modal and grain-size variation in layered intrusions.

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Articles
Information
Geological Magazine , Volume 119 , Issue 4 , July 1982 , pp. 405 - 412
Copyright
Copyright © Cambridge University Press 1982

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References

Esbensen, K. H. 1978. Trace element distribution during extreme differentiation in the Fongen–Hyllingen gabbro complex, Trondheim Region, Norway. J. geol. Soc. Lond. 135, 593–4 (abstract).Google Scholar
Grove, T. L. & Bence, A. E. 1977. Experimental study of pyroxene–liquid interaction in quartz-normative basalt 15597. Proc. Eighth Lunar Sci. Conf. 1549–79.Google Scholar
Hawkes, D. D. 1967. Order of abundant crystal nucleation in a natural magma. Geol. Mag. 104, 473–86.CrossRefGoogle Scholar
Hess, H. H. 1960. Stillwater Igneous Complex, Montana. A quantitative mineralogical study. Mem. geol. Soc Am. 80.Google Scholar
Holloway, J. R. & Burnham, C. W. 1972. Melting relations of basalt with equilibrium water pressure less than total pressure. J. Petrology 13, 1–29.CrossRefGoogle Scholar
Irving, T. N. 1974. Petrology of the Duke Island Ultramafic Complex, Southeastern Alaska. Mem. geol. Soc Am. 138.Google Scholar
Jackson, E. D. 1961. Primary textures and mineral associations in the Ultramafic Zone of the Stillwater Complex, Montana. Prof. Pap. U.S. geol. Surv. 358.Google Scholar
Jackson, E. D. 1971. The origin of ultramafic rocks by cumulus processes. Fortsch. Miner. 48, 128–74.Google Scholar
Jorgenson, D. B. 1979. Textural banding in igneous rocks: an example from southwestern Oregon. Am. Miner. 64, 527–30.Google Scholar
Maaløe, S. 1978. The origin of rhythmic layering. Mineralog. Mag. 42, 337–45.CrossRefGoogle Scholar
Matthews, D. W. 1976. Post-cumulus disruption of the Lilloise Intrusion, East Greenland. Geol. Mag. 113, 287–96.CrossRefGoogle Scholar
McBirney, A. R. & Noyes, R. M. 1979. Crystallization and layering of the Skaergaard Intrusion. J. Petrology 20, 487–554.CrossRefGoogle Scholar
Morse, S. A. 1969. The Kiglapait Layered Intrusion, Labrador. Mem. geol. Soc. Am. 112.Google Scholar
Nwe, Y. Y. 1975. Two different pyroxene crystallisation trends in the trough bands of the Skaergaard Intrusion, East Greenland. Contr. Miner. Petr. 49, 285–300.CrossRefGoogle Scholar
Olesen, N. Ø., Hansen, E. S., Kristensen, L. H. & Thyrsted, T. 1973. A preliminary account on the geology of the Selbu–Tydal area, the Trondheim region, central Norwegian Caledonides. Leidse geol. Meded. 49, 259–76.Google Scholar
Page, N. J. 1979. Stillwater Complex, Montana – structure, mineralogy, and petrology of the basal zone with emphasis on the occurrence of sulfides. Prof. Pap. U.S. geol. Surv. 1038.Google Scholar
Page, N. J., Shimek, R. & Huffman, C. 1972. Grain-size variations within an olivine cumulate, Stillwater Complex, Montana. Prof. Pap. U.S. geol. Surv. 800-C, C29–37.Google Scholar
Parsons, I. 1979. The Klokken Gabbro-Syenite Complex, South Greenland: cryptic variation and origin of inversely graded layering. J. Petrology 20, 653–94.CrossRefGoogle Scholar
Read, H. H., Sadashivaiah, M. S. & Haq, B. T. 1965. The hypersthene-gabbro of the Insch Complex, Aberdeenshire. Proc. Geol. Ass. 76, 1–11.CrossRefGoogle Scholar
Roobol, M. J. 1972. Size-graded, igneous layering in an Icelandic intrusion. Geol. Mag. 109, 393–404.CrossRefGoogle Scholar
Stephenson, D. 1974. Mn and Ca enriched olivines from nepheline syenites of the South Qoroq Centre, south Greenland. Lithos 7, 35–41.CrossRefGoogle Scholar
Thy, P. & Esbensen, K. H. 1982. Origin of certain types of small-scale igneous layering from the Fongen–Hyllingen basic complex, Norway. Geol. För. Stockh. Förh. 104 (In the press).CrossRefGoogle Scholar
Thy, P. & Wilson, J. R. 1980. Primary igneous load cast deformation structures from the Fongen–Hyllingen layered gabbro, Trondheim Region, Norway. Geol. Mag. 117, 363–71.CrossRefGoogle Scholar
Wager, L. R. 1961. A note on the origin of ophitic textures in the chilled olivine gabbro of the Skaergaard Intrusion. Geol. Mag. 98, 353–66.CrossRefGoogle Scholar
Wager, L. R. 1963. The mechanism of adcumulus growth in the layered series of the Skaergaard intrusion. Spec. Pap. geol. Soc. Am. 1, 1–9.Google Scholar
Wager, L. R. & Brown, G. M. 1967. Layered Igneous Rocks. San Francisco: Freeman.Google Scholar
Wager, L. R., Brown, G. M. & Wadsworth, W. J. 1960. Types of igneous cumulates. J. Petrology 1, 73–85.CrossRefGoogle Scholar
Wilson, J. R., Esbensen, K. H. & Thy, P. 1981. Igneous petrology of the synorogenic Fongen–Hyllingen layered basic complex, Southern Norwegian Caledonides. J. Petrology 22, 584–627.CrossRefGoogle Scholar
Wilson, J. R. & Olesen, N. O. 1975. The form of the Fongen–Hyllingen gabbro complex, Trondheim Region, Norway. Norsk geol. Tidsskr. 55, 423–39.Google Scholar