Experimental study of different modes of block sliding along interface. Part 2. Field experiments and phenomenological model of the phenomenon
- Authors: Kocharyan G.G.1,2, Ostapchuk A.A.1, Pavlov D.V.1, Ruzhich V.V.3, Batukhtin I.V.1,2, Vinogradov E.A.1, Kamai A.M.2, Markov V.K.1
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Affiliations:
- Institute of Geosphere Dynamics
- Moscow Institute of Physics and Technology (State University)
- Institute of the Earth’s Crust, Siberian Branch
- Issue: Vol 20, No 2 (2017)
- Pages: 193-202
- Section: Article
- URL: https://journals.rcsi.science/1029-9599/article/view/191525
- DOI: https://doi.org/10.1134/S1029959917020096
- ID: 191525
Cite item
Abstract
The paper reports the results of field experiments on studying different modes of gravitational sliding of a block on the natural fault surface. Various materials were used as interface filler to model the whole range of deformation events that can be arbitrarily divided into three groups: accelerated creep, slow slip, and dynamic slip. The experiments show that the type of modeled deformation events is defined by both structural parameters of contact between blocks and material composition of the contact filler.
Foundations for a new geomechanical model of occurrence of different-type dynamic events were developed. The model is based on the idea that “contact spots” form subnormally to the crack edges during shear deformation; the “spots” are clusters of force mesostructures whose evolution governs the deformation mode. The spatial configuration of “contact spots” remains unchanged during the entire “loading-slip” cycle but changes after the dynamic event occurrence. The destroyed force mesostructures can be replaced by similar structures under intergranular interaction forces when the external influence is fully compensated. Unless “contact spots” are incompletely destroyed, the deformation process dynamics is defined by their rheology. The migration of “contact spots” during deformation of a crack filled with heterogeneous material causes changes in deformation parameters and transformation of the mode itself due to changing rheology of local contact areas between blocks.
It is found by fractal analysis that in order for dynamic slip to occur, spatially structured “contact spots” characterized by low fractal dimension must be formed; slow slip events can exist only in a certain parametric domain called the “dome of slow events”. It is found that the probability of slow slip occurrence is higher on fault regions characterized by maximum fractal dimension values: fault tips, fault branching and fault intersection zones.
Keywords
About the authors
G. G. Kocharyan
Institute of Geosphere Dynamics; Moscow Institute of Physics and Technology (State University)
Author for correspondence.
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334; Moscow, 117303
A. A. Ostapchuk
Institute of Geosphere Dynamics
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334
D. V. Pavlov
Institute of Geosphere Dynamics
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334
V. V. Ruzhich
Institute of the Earth’s Crust, Siberian Branch
Email: gevorgkidg@mail.ru
Russian Federation, Irkutsk, 664033
I. V. Batukhtin
Institute of Geosphere Dynamics; Moscow Institute of Physics and Technology (State University)
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334; Moscow, 117303
E. A. Vinogradov
Institute of Geosphere Dynamics
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334
A. M. Kamai
Moscow Institute of Physics and Technology (State University)
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 117303
V. K. Markov
Institute of Geosphere Dynamics
Email: gevorgkidg@mail.ru
Russian Federation, Moscow, 119334