Fluid Mechanics of Intrusives


The fluid mechanics of dike emplacement are analyzed using the translatory wave theory. The stress strain relations in the host rock are assumed linear and the fracture resistance of the host rock is assumed small. The resulting model is a flowing dyke progressing upwards to the surface with constant speed and a very small side slope. Apart from the topmost section, the form of the dyke is very close to the static form corresponding to the magma pressure in a no-flow situation. Two scales are found that control the flow, a width scale and a composite stiffness parameter for the host rock, representing the properties of the rock and the magma such as elasticity and viscosity. The theory explains a number of special features for dykes that are already known by researchers. It also adds two new points, the most interesting being that the composite stiffness of the rock can be estimated from field observations of the downwards widening angle of the dyke.

Share and Cite:

Elíasson, J. (2013) Fluid Mechanics of Intrusives. International Journal of Geosciences, 4, 9-14. doi: 10.4236/ijg.2013.410A002.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] J. R. Lister and R. C. Kerr, “Fluid—Mechanical Models of Crack Propagation and Their Application to Magma Transport in Dykes,” Journal of Geophysical Research: Solid Earth (1978-2012), Vol. 96, No. B6, 1991, pp. 10049-10077.
[2] J. L. Kavanagh, R. Sparks and J. Stephen, “Insights of Dyke Emplacement Mechanics from Detailed 3D Dyke Thickness,” Journal of the Geological Society, Vol. 168, No. 4, 2011, p. 965.
[3] A. Gudmundsson, “Formation of Dykes, Feeder-Dykes, and the Intrusion of Dykes from Magma Chambers,” Bulletin Volcanologique, Vol. 47, No. 3, 1984, pp. 537-550.
[4] S. R. Spengler and G. P. L. Dike, “Width Characteristics Observed in Intraplate Volcanoes,” 2012.
[5] A. M. Rubin, “Propagation of Magma-Filled Cracks,” Annual Review of Earth and Planetary Sciences, Vol. 23, 1995, pp. 287-336.
[6] H. E. Huppert and R. S. J. Sparks, “The Generation of Granitic Magmas by Intrusion of Basalt into Continental Crust,” Journal of Petrology, Vol. 29, No. 3, 1988, pp. 599-624. http://dx.doi.org/10.1093/petrology/29.3.599
[7] D. A. Spence and D. L. Turcotte, “Magma-Driven Propagation of Cracks,” Journal of Geophysical Research: Solid Earth (1978-2012), Vol. 90, No. B1, 1985, pp. 575-580.
[8] G. P. L. Walker, “The Structure of Eastern Iceland,” In: L. Kristjansson, Ed., Geodynamics of Iceland and the North Atlantic Area (NATO ASI volume C11), Reidel Publ. Co., Dordrecht, 1974, pp. 177-188.
[9] J. Elíasson, S. P. Kjaran, S. L. Holm, M. T. Gudmundsson and G. Larsen, “Large Hazardous Floods as Translatory Waves,” Environmental Modelling & Software, Vol. 22, No. 10, 2007, pp. 1392-1399.
[10] J. Elíasson, G. Guigay and B. Karlsson, “Enclosure Fires, Gravity Waves, and the Backdraft Problem,” Journal of Fire Sciences, Vol. 26, No. 5, 2008, pp. 373-397.
[11] J. Elíasson, “A Glacial Burst Tsunami near Vestmannaeyjar, Iceland,” Journal of Coastal Research, Vol. 24, No. 1, 2008, pp. 13-20.
[12] D. D. Pollard and O. H. Muller, “The Effect of Gradients in Regional Stress and Magma Pressure on the Form of Sheet Intrusions in Cross Section,” Journal of Geophysical Research, Vol. 81, No. 5, 1976, pp. 975-984.
[13] M. Olafsson, G. A Berufjardarstond, “4th Year Science Project,” University of Iceland, 1977.

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.