Roman Teisseyre

Earthquake source asymmetry, structural media and rotation effects

Macroseismic Rotation Effects and Micromotions.- Development of Earthquake Rotational Effect Study.- Sources of Rotation and Twist Motions.- Some Examples of Rotation Effects: the Tulbagh Earthquake, South Africa.- Theory of Continua and Fields of Defects.- Deviations from Symmetry and Elasticity: Asymmetric Continuum Mechanics.- Degenerated Asymmetric Continuum Theory.- Continuum with Rotation Nuclei and Defects: Dislocation and Disclination Densities.- Towards a Discrete Theory of Defects.- Fault Dynamics and Related Radiation.- A Review on Friction.- Soliton Physics.- Rotation Motions, Seismic Source Models, and Asymmetry of Fracture.- Rotational Motions Excited by Earthquakes.- Ground Rotational Motions Recorded in Near-Source Region of Earthquakes.- Fracture-Band Geometry and Rotation Energy Release.- Rotation Motions: Recording and Analysis.- Glacier Motion: Seismic Events and Rotation/Tilt Phenomena.- Rotational Energy and Angular Momentum of Earthquakes.- Bend-Rotation Wave as a Mechanism of Macroseismic Effects.- Solitary Waves in Crustal Faults and their Application to Earthquakes.- Seismic Rotation Waves: Spin and Twist Solitons.- Earth Rotation, Elasticity and Geodynamics: Earthquake Wave Rotary Model.- Effects Related to Medium Structures and Complexity of Wave Propagation.- Seismic Rotation Waves in the Continuum with Nonlinear Microstructure.- Tectonic Solitons Propagating Along the Fault.- Complexity of Rotation Soliton Propagation.- Micromorphic Continuum with Defects and Taylor-Bishop-Hill Theory for Polycrystals: Anisotropic Propagation of Seismic Waves and the Golebiewska Gauge.- Seismic Ray Theory for Structural Medium based on Kawaguchi and Finsler Geometry.- From Non-Local to Asymmetric Deformation Field.- Earthquake Hazard in the Valley of Mexico: Entropy, Structure, Complexity.- Seismic Rotational Motions: Recording Techniques and Data Analysis.- Note on the Historical Rotation Seismographs.- Ring Laser Gyroscopes as Rotation Sensors for Seismic Wave Studies.- Rotational Motions in Seismology: Theory, Observation, Simulation.- Absolute Rotation Measurement Based on the Sagnac Effect.- Design of Rotation Seismometer and Non-Linear Behaviour of Rotation Components of Earthquakes.- Rotation and Twist Motion Recording - Couple Pendulum and Rigid Seismometers System.- Equation of Pendulum Motion Including Rotations and its Implications to the Strong-Ground Motion.- Strong Motion Rotation Sensor.- High-Resolution Wide-Range Tiltmeter: Observations of Earth Free Oscillations Excited by the 26 December 2004 Sumatra -Andaman Earthquake.- Fiber Optic Sensors for Seismic Monitoring.- Rotations and Engineering Seismology.- Deriving Seismic Surface Rotations for Engineering Purposes.- Effects of Torsional and Rocking Excitations on the Response of Structures.

Earthquake processes in a micromorphic continuum

SummaryThe paper introduces a new model earthquake process based on the theory of micromorphic continua. The processes in a focal region are described by deformations of microstructure in time. It is assumed that the fracturing processes as well as phase transformation of metamorphic phenomena have caused in the past certain non-reversible changes which determine the microstructure of focal region. These internal microstructural elements form the attaching points around which the couple stresses arise. The properties of focal region are determined by the constitutive equations. The micromorphic mechanics considers the existence of body couples as determined by a regional stresses and looks after a response field of stresses, stress moments and strains in the focal region. Further, it is explained how microdislocation field is connected with microdeformations and micromorphic structure. In the considered earthquake structure model a microanisotropy is assumed through the tensor of microinertia. This tensor describes a distribution of microelements. Simple solutions of wave processes in a focal region are presented. The dispersion of waves is discussed.

Tutorial on New Developments in the Physics of Rotational Motions

Abstract We present a linear continuum theory incorporating asymmetric stress fields as well as symmetric strains and antisymmetric rotations. We discuss the related constitutive laws and balance equations. In this theory, the motion equation related to the balance of the antisymmetric part of stresses replaces that for the stress moments. Our theory proves that the rotation waves may exist even in a homogeneous elastic continuum. Different kinds of extreme deformations are considered. The wave solutions, including the coaction of the rotation and twist fields, are presented and discussed. The dislocation density–stress relations are derived with the help of the symmetric and antisymmetric parts of stresses. The synchronization solution, rotation, and twist, shifted in phase by π /2, are presented for a material in an advanced deformation state with granulation and microcracking. Some examples of the spin and twist motion records are reported that confirm this synchronization hypothesis.

Continua with self-rotation nuclei: evolution of asymmetric fields

Abstract We present a consistent theory of continua with defect distribution including the density of rotation nuclei. The elastic and self-fields of stresses and strains become asymmetric; the tensor of incompatibility also becomes asymmetric. We derive the dislocation–stress relations and the equations of motion related to the momentum and moment of momentum. Some applications important for earthquake engineering are presented.

Fundamental Deformations in Asymmetric Continuum

Abstract The complexity of processes in a seismic source zone has inspired us to reconsider a class of basic motions and deformations in an asymmetric continuum, including simple motions (translation and rotation, named spin) and simple deformations. Simple deformations include the axial nuclei, that is, point extension/compression, and the shear nuclei related to string-string point deformations. The point deformation is further redefined as another kind of rotational motion, called twist, representing oscillations of the main shear axes and their amplitudes. Some remarks are added on the recording systems used to measure these motions and deformations.

Why Rotation Seismology: Confrontation between Classic and Asymmetric Theories

Abstract We present a confrontation between the classic elasticity and asymmetric continuum theories in order to point out the abilities of the two approaches and their deficiencies. The role of independent strain and rotation waves is discussed and some related particular examples are given.

Micromorphic Continuum and Fractal Fracturing in the Lithosphere

—It seems that internal structures and discontinuities in the lithosphere essentially influence the lithospheric deformation such as faulting or earthquakes. The micromorphic continuum provides a good framework to study the continuum with microstructure, such as earthquake structures. Here we briefly introduce the relation between the theory of micromorphic continuum and the rotational effects related to the internal microstructure in epicenter zones. Thereafter the equilibrium equation, in terms of the displacements (the Navier equation) in the medium with microstructure, is derived from the theory of the micromorphic continuum. This equation is the generalization of the Laplace equation in terms of displacements and can lead to Laplace equations such as the local diffusion-like conservation equations for strains. These local balance/stationary state of strains under the steady non-equilibrium strain flux through the plate boundaries bear the scale-invariant properties of fracturing in the lithospheric plate with microstructure.

Physics of Asymmetric Continuum: Extreme and Fracture Processes

to Asymmetric Continuum and Experimental Evidence of Rotation Motions.- to Asymmetric Continuum: Fundamental Point Deformations.- Measurement of Short-Period Weak Rotation Signals.- Buildings as Sources of Rotational Waves.- Two-Pendulum Systems for Measuring Rotations.- Theory and Observations: Some Remarks on Rotational Motions.- Continuum with Defect Densities and Asymmetry of Fields.- Field Invariant Representation: Dirac Tensors.- Asymmetric Continuum: Standard Theory.- Fracture Processes: Spin and Twist-Shear Coincidence.- Inplane and Antiplane Fracturing in a Multimode Random Sequence.- 10 Charged Dislocations and Various Sources of Electric Field Excitation.- Friction and Fracture Induced Anisotropy: Asymmetric Stresses.- Asymmetric Fluid Dynamics: Extreme Phenomena.- Fracture Band Thermodynamics.- Interaction Asymmetric Continuum Theory.- Fracture Physics Based on a Soliton Approach.- Canonical Approach to Asymmetric Continua.- Deformations in Riemannian Geometry.- Continuum Theory of Defects: Advanced Approaches.- Spinors and Torsion in a Riemann-Cartan Approach to Elasticity with a Continuous Defect Distribution and Analogies to the Einstein-Cartan Theory of Gravitation.- Twistors as Spin and Twist Solitons.- Potentials in Asymmetric Continuum: Approach to Complex Relativity.

Fracture-Band Geometry and Rotation Energy Release

The fracture processes are determined by stress load and local stress concentrations due to accumulation of dislocations and partial mutual dislocation annihilations. In such processes, the formation of dislocation arrays and microcracks related to the premonitory processes and its rebound event plays an essential role. Additional counterpart of stress moments appears due to the antisymmetric stresses related grain rotations and due to stress moments formed by the fracturing pattern.

New earthquake rebound theory

Abstract The model adopted in this paper assumes that a medium is permeated with a continuum field of defects and that a flow of defects describes an advanced state of deformation leading to fracturing. The obtained system of equations describes a field of internal stresses and a relative flow velocity of cracks. The form of equations shows that before an earthquake a field of internal stresses reaches its maximum and that this moment corresponds to a specific silent gap expressed by the disappearance of the relative velocity field of cracks. Later on there starts a rebound process with an opposite sense of relative velocities, with decrease of defect density (joining of cracks) and with a main process of earthquake release.