The effect of oriented microcracks and crystallographic and shape preferred orientation on bulk elastic anisotropy of a foliated biotite gneiss from Outokumpu

Kern, H.; Ivankina, T. I.; Nikitin, A. N.; Lokajı́ček, T.; Pros, Z.

doi:10.1016/j.tecto.2008.06.015

Cited by 83 publications

(80 citation statements)

References 16 publications

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“…Kern et al, 2002;Pros et al, 2003;Ivankina et al, 2005;Ullemeyer et al, 2006;Kern et al, 2008). The unique experiments of Christensen (1974) on mantle rocks confirmed crack influence to pressures of about 1 GPa, and there is evidence from lowpressure measurements that crack influence up to 1 GPa (or more) is valid for other rock types as well (Ullemeyer et al, 2011).…”

Section: Accepted M Manuscriptmentioning

confidence: 70%

Crystallographic preferred orientations of exhumed subduction channel rocks from the Eclogite Zone of the Tauern Window (Eastern Alps, Austria), and implications on rock elastic anisotropies at great depths

et al. 2015

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Section: Accepted M Manuscriptmentioning

confidence: 70%

Crystallographic preferred orientations of exhumed subduction channel rocks from the Eclogite Zone of the Tauern Window (Eastern Alps, Austria), and implications on rock elastic anisotropies at great depths

et al. 2015

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“…), their strong CPO and the very high anisotropy of both minerals (>40%). It should be noted that shape preferred orientation (SPO) of biotite and muscovite as well as oriented microcracks may also contribute to bulk anisotropy [17][18][19].…”

Section: Laboratory Measurements Of P-and S-wave Velocitiesmentioning

confidence: 99%

Measuring and Modeling of P- and S-Wave Velocities on Crustal Rocks: A Key for the Interpretation of Seismic Reflection and Refraction Data

Kern

2011

International Journal of Geophysics

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Lithologic interpretations of the earth crust from seismic wave velocities are non-unique so that inferences about composition can not be drawn. In order to evaluate how elastic properties of rock materials are controlled by lithology at in situ pressures and temperatures, compressional (Vp), shear wave velocities (Vs) and velocity anisotropy of crustal rocks were measured at conditions of greater depth. The first part deals with the interdependence of elastic wave propagation and the physical and lithological parameters. In the second part data from laboratory seismic measurements and theoretical calculations are used to interpret (1) a shallow seismic reflection line (SE Finland) and (2) a refraction profile of a deep crust (Central China). The comparison of the calculated velocities with the experimentally-derived in situ velocities of the Finnish crustal rocks give hints that microcracks have an important bearing on the in situ seismic velocities, velocity anisotropy and the reflectivity observed at relative shallow depth. The coupling of the experimentally-derived in situ velocities of P-and S-wave and corresponding Poisson's ratios of relevant exhumed high-grade metamorphic crustal rocks from Central China with respective data from seismic refraction profiling provided a key for the lithologic interpretation of a deep seismic crustal structure.

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“…Commonly, bulk elastic properties of multiphase polycrystalline rocks are assessed with simple averaging models such as Voigt, Reuss, and Hill, which are not able to account for the effects of grain shapes in the elastic properties (e.g., Ivankina et al, 2005;Kern et al, 2008;Wang et al, 2009). These models perform averaging of single crystal elastic properties of different minerals over their crystal orientation distribution functions (ODFs) that relate the crystal orientations relative to sample coordinates.…”

Section: Introductionmentioning

confidence: 99%

“…These models perform averaging of single crystal elastic properties of different minerals over their crystal orientation distribution functions (ODFs) that relate the crystal orientations relative to sample coordinates. Also, it is commonly believed that oblate plate grain shape of sheet silicates and corresponding shape orientation distributions will lead to an increase in the calculated elastic anisotropy of rocks (e.g., Kern et al, 2008). Consideration of grain shapes is possible within mean-field, selfconsistent models, based on Eshelby's concept of ellipsoidal inclusions in a matrix (Eshelby, 1957).…”

Section: Introductionmentioning

confidence: 99%

The influence of grain shape and volume fraction of sheet silicates on elastic properties of aggregates: Biotite platelets in an isotropic matrix

et al. 2014

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Elastic anisotropy of sheet-silicate-rich rocks such as shales and slates strongly depends on the orientation distribution of platelet-shaped minerals, as well as shape and orientation of pores. Bulk elastic anisotropy of the rock results in the anisotropy with respect to the propagation of elastic waves, and consequently, the fastest P-waves can travel with velocities exceeding the slowest velocities by a factor of two or even greater. An important factor is the sheet-silicate's grain shapes. We approached a model system of biotite platelets in an isotropic matrix with different methods: A mean-field self-consistent method that considered ellipsoidal particles in an effective anisotropic matrix, and a full-field method based on fast Fourier transforms that considered the microstructure, the topology of the polycrystal, and local interactions. Both methods provided numerically very close results. Using these results, we predicted that the aggregate with more oblate grain shape (thinner platelets) was elastically more anisotropic than the material with grains of less oblate shape, but only for small volume fractions of oriented platelets. For large fractions of platelets, the opposite was true. This switchover in the elastic anisotropy depended on texture strength, platelet shape, and elastic properties of the isotropic matrix.

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The effect of oriented microcracks and crystallographic and shape preferred orientation on bulk elastic anisotropy of a foliated biotite gneiss from Outokumpu

Cited by 83 publications

References 16 publications

Crystallographic preferred orientations of exhumed subduction channel rocks from the Eclogite Zone of the Tauern Window (Eastern Alps, Austria), and implications on rock elastic anisotropies at great depths

Crystallographic preferred orientations of exhumed subduction channel rocks from the Eclogite Zone of the Tauern Window (Eastern Alps, Austria), and implications on rock elastic anisotropies at great depths

Measuring and Modeling of P- and S-Wave Velocities on Crustal Rocks: A Key for the Interpretation of Seismic Reflection and Refraction Data

The influence of grain shape and volume fraction of sheet silicates on elastic properties of aggregates: Biotite platelets in an isotropic matrix

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