Steady state creep of fine grain granite at partial melting

Main Article Content

F. Auer
H. Berckhemer
G. Oehlschlegel


Steady state creep under constant stress has been measured in a fine grain granite (aplite) from Schauinsland, Germany for the temperature range of partial melting 860°–1060°C, under a hydrostatic pressure of 4.2 kbar, and at low shear stresses of 5–50 bar. The apparatus used is described briefly. Rheological measurements are complemented by microscopic investigations. With a melt fraction of up to about 20%, creep can be described by a power law with a stress exponent of 3-4 and an activation energy of 80 kcal/mole, typical for creep in solids. Above 1010°C or 20% melt, the activation energy increases rapidly to a value of 200 kcal/mole simultaneously with a rapid increase of the melt fraction and a decrease of feldspar content. From the grain structure and from etching tests it is concluded that quartz contributes little to the plastic deformation which is governed mainly by the stress and temperature induced recrystallization of feldspar. The large temperature dependence of the creep rate above 1010° C may be caused by the decreasing area of grain contacts and consequent rise in local stress. These results support those of Arzi (1974) and Roscoe (1952).

Google Scholar           ARK:



Article Details

How to Cite
Auer, F., Berckhemer, H., & Oehlschlegel, G. (1981). Steady state creep of fine grain granite at partial melting. Journal of Geophysics, 49(1), 89-92. Retrieved from
Bookmark and Share


Arzi, A. (1974) Partial melting in rocks: rheology, kinetics, water diffusion. Ph.D. Thesis, Harvard University

Arzi, A. (1978) Critical phenomena in the rheology of partially melted rocks. Tectonophysics 44:173-184

Berckhemer, H., Auer, F., Drisler, J. (1979) High temperature anelasticity and elasticity of mantle peridotite. Phys. Earth Planet. Inter. 20:48-59

Carter, N. (1976) Steady state flow of rocks. Rev. Geophys. Space Phys. 14:301-360

Goetze, C. (1977) A brief summary of our present day understanding of the effect of volatiles and partial melt on the mechanical properties of the upper mantle. In: Manghnani, M.H., Akimoto, S.I. (Eds.) High pressure research, pp. 3-24. New York, Academic Press

Molen, I. Van der, Paterson, M.S. (1979) Experimental deformation of partially melted granite. Contrib. Mineral. Petrol. 70:299-318

Paterson, M.S. (1979) The mechanical behaviour of rock under crustal and mantle conditions. In: McElhinny, M.W. (Ed.) The Earth, its origin, structure and evolution. Academic Press, New York

Press, F. (1959) Some implications of mantle and crustal structure from G waves and Love waves. J. Geophys. Res. 64:565-568

Ringwood, A.E. (1969) Composition and evolution of the upper mantle. In: Hart, P.J. (Ed.) The Earth's Crust and Upper Mantle, Geophys. Monogr. 13:1-17. Am. Geophys. Union, Wash. D.C.

Ritsema, A.R. (1972) Synopsis of some comments on Sir Herold Jeffrey's paper on creep in the Earth and planets. Tectonophysics 13:579-580

Roscoe, R. (1952) The viscosity of suspension of rigid spheres. Br. J. Appl. Phys. 3:267-269

Weertman, I., Weertman, I.R. (1975) High temperature creep of rock and mantle viscosity. Annu. Rev. Earth Planet. Sci. 3:293