Abstract
The maximum entropy method is used to infer the dimensions of cracks in granitic rocks from measurements made under confining pressure of their hydraulic permeability and of their electrical conductivity. The fluctuations of crack dimensions are characterized by a crack spectrum which gives the frequency of occurrence of cracks as a function of their cross-sectional length and aspect ratio in the absence of stress. First, using an effective medium approximation, the variations of the transport coefficients resulting from crack deformation under pressure are expressed by averaging the pressure-dependent crack electrical or hydraulic contributions over the unknown crack spectrum. Next, the maximum entropy crack spectrum in Westerly granite is determined from laboratory measurements of the transport coefficients. The predicted spectrum is comparable to the distribution of dimensions estimated from direct observations of cracks with a scanning electron microscope. The main features of the calculated spectrum are interpreted from a model of growth of the microfissures during cooling of the granite.
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© 1988 Kluwer Academic Publishers
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Doyen, P.M. (1988). Maximum Entropy and Crack Geometry in Granitic Rocks. In: Erickson, G.J., Smith, C.R. (eds) Maximum-Entropy and Bayesian Methods in Science and Engineering. Fundamental Theories of Physics, vol 31-32. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-9054-4_23
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DOI: https://doi.org/10.1007/978-94-010-9054-4_23
Publisher Name: Springer, Dordrecht
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