Viscosity is one of the important material properties of the Earth, controlling tectonic and dynamic processes such as mantle convection, isostasy, and glacial rebound. Yet it remains a poorly resolved parameter and basic questions such as whether the planet's response to loading is linear or non-linear, or what are its depth and lateral variations remain uncertain.

Сборник посвящен 75-летию Е.И. Шемякина. В сборник включены статьи по теории упругости, теории пластичности и ползучести, механике разрушения, реологии, горным наукам, геомеханике, механическим свойствам и разрушению геоматериалов и горных массивов и др. Статьи отражают современное состояние вопросов механики деформируемых твердых тел и горных пород, а также её приложений.
Для научных работников, аспирантов, студентов старших курсов, специализирующихся в области механики деформируемых твердых тел и горных пород.

В книге рассмотрены теоретические основы реологии твердых деформируемых тел, даны сведения о глинистых грунтах, изложены их основные реологические свойства. Обобщены результаты исследований реологических свойств обыкновенных, просадочных и набухающих глинистых грунтов с учетом ряда особых воздействий. Описаны приборы и методы экспериментирования, изложены результаты обработки опытных данных, получены простые и удобные для практического приложения физические соотношения.
Рассчитана на широкий круг научных, инженерно-технических работников и аспирантов научно-исследовательских, проектных и изыскательских организаций, занимающихся исследованием механических и реологических свойств грунтов, а также студентов строительных и инженерно-геологических специальностей вузов.

Обобщены результаты исследований в области экспериментальной реологии - ползучести и длительной прочности обыкновенных, просадочных и набухающих глинистых грунтов. Рассмотрены вопросы реологии твердых тел, теорий ползучести материалов, природы- прочности и деформируемости, физических и водных свойств глинистых грунтов.

Martin Casey, who died on the 10 June 2008 after a short illness, was a structural geologist of world renown. He led numerical approaches to understanding rock deformation and the development of tectonic structures, pioneering the quantitative analysis of rock fabrics, textures and folds. These researches now underpin diverse areas of geology, such as quantifying the strength of rocks in the crust which leads to calibrations of the seismic properties of the minerals in continents and the prediction of the fine-scale structure of hydrocarbon reservoirs. This Special Publication is dedicated to his memory not only for his fundamental contribution to science but also as a mentor, colleague and friend. <...>

It is my great pleasure to introduce this volume dedicated to my long-standing colleague and friend, Henk Zwart; the more so since I missed the opportunity of addressing him on the occasion of his retirement from the chair of structural and applied geology in the State University at Utrecht in 1988.

This volume is derived from the 13th meeting on Deformation Mechanisms, Rheology and Tectonics (DRT2003). The meeting was held in St Malo (Brittany, France) in April 2003, and organized by an informal group from Gdosciences Rennes (UMR 6118 CNRS, Rennes University), including Michel Ballbvre, St6phane Bonnet, Arlette Falaise, Olivier Galland, Fr6d6ric Gueydan, Charles Gumiaux, Benjamin Le Bayon, Alain-Herv6 Le Gall, Monique Le Moigne, Sylvie Schueller, and C61ine Tirel. It was sponsored by the Centre National de la Recherche Scientifique, Rennes University, the ity of Rennes, the Conseil G6n6ral d'Ille et Vilaine, and the R6gion Bretagne. Forty-eight reviewers have worked hard to improve the papers. We thank these persons and institutions for their contributions.

Обобщены результаты экспериментальных исследований, полученные в области реологии глинистых грунтов и связанные с использованием глинистых оснований при возведении крупных объектов промышленного и гражданского строительства. Рассмотрены вопросы реологии твердых тел, их деформации и прочности. Изложены основы теорий ползучести и релаксации напряжений, даны краткие сведения о глинистых грунтах и протекающих в них реологических явлениях в природных условиях. Описаны методы определения мгновенных и ползучих деформаций, избыточного давления в поровой воде, бокового давления и объемных деформаций. Изложены вопросы влияния уплотняющего давления глинистых грунтов на их реологические свойства.

Для инженерно-технических и научных работников, занимающихся вопросами изучения свойств глинистых грунтов, проектированием гражданских, промышленных, гидротехнических сооружений и т.п.

This study aims at further understanding of the mechanisms how lattice-preferred orientations (LPO) develop during deformation in the main eclogite minerals. Microstructures and textures of deformed eclogites from the Les Essarts complex (Western France) were investigated using optical microscopy and electron backscatter diffraction (EBSD) in the scanning electron microscope. Microfabric analyses of eclogite-facies minerals are used to identify their deformation mechanisms, which define the rheology at high-pressure metamorphic conditions. Mechanisms of intracrystalline deformation by dislocation movement (dislocation creep) result usually in a non-linear flow law (typically power law), while diffusive processes (diffusion creep) correspond to linear flow laws. General microstructural observations may suggest intracrystalline deformation (dislocation creep) of omphacite. The omphacite LPO vary between S- and L-type and correlate with oblate or prolate grain shape fabrics, respectively. Until now, these LPO types have not been understood by plasticity models based on dislocation glide on the known slip systems in clinopyroxene. An alternative interpretation is given in terms of anisotropic growth and dissolution, with grain boundary diffusion as the rate controlling process. There are further indications suggesting diffusion creep with concomitant anisotropic growth and dissolution as a main deformation mechanism in omphacite. In omphacite around a hollow garnet, crystallographic and shape fabrics align with the c[001] axes parallel to the grain elongations defining the mineral lineation, which rotates locally with the inferred flow direction. In this part, the grain sizes of omphacite and rutile are larger than in the surrounding matrix. The geometry of both the shape and crystallographic fabrics is interpreted to represent the local stress regime (directions and ratios of the principal stresses). The LPO of rutile duplicate the LPO of omphacite and a similar distinction between S- and L-type was used. Rutile deformation mechanisms probably involve dislocation creep as well as diffusion creep. Quartz mainly occurs as an interstitial phase with weak LPO patterns interpreted as random. No representative obliquity of the LPO in omphacite nor rutile with respect to foliation and lineation was observed to be used as potential shear sense criteria. However, the rutile LPO was slightly rotated relative to the omphacite LPO consistently in most samples. The results suggest that diffusion processes are strongly involved in the deformation of eclogites. A linear flow law should be taken into account in tectonic models where eclogites are incorporated. 

This paper presents a detailed comparison of the microboudinage of piedmontite in two different mineralogical hosts, a quartz matrix, and albite porphyroblasts in a siliceous schist, with the aim of clarifying the rheological properties of albite in relation to those of quartz. Stress and strain analyses of the microboudinage confirm that the boudinage took place in the retrograde stage of metamorphism during decreasing temperature, and reveal that albite deformed at the same strain rate as quartz above the plastic-brittle transition temperature of albite.