Alexey Dm. Zavyalov

Russian Academy of Sciences | RAS · Institute of Physics of the Earth

One hundred years ago, Fusakichi Omori died. Our paper is dedicated to his memory. Omori made an outstanding contribution to the physics of earthquakes. In 1894 he formulated the law of aftershock evolution. Omori’s Law states that after the main shock of an earthquake, the frequency of aftershocks decreases hyperbolically with time. In this paper,...

This paper continues a series of publications on the modification of the Map of Expected Earthquakes (MEE), a method of medium-term earthquake forecasting. It is devoted to the calculation and analysis of retrospective statistical characteristics of dynamic and quasi-stationary prognostic indicators in the Kamchatka region, used at this stage in th...

This article is the second in a series devoted to the modification of the Map of Expected Earthquakes (MEE) method of medium-term earthquake forecasting. The description of algorithms for preparing and analyzing initial data and the results of their application are presented. In particular, the following additional functional capabilities have bee...

Dear Colleagues, Despite some success, the issue of earthquake forecasting has yet to be resolved. There are occasional discussions within the scientific community about the principal feasibility of earthquake forecasting, particularly in the short-term aspect. However, the bulk of these discussions were set in the Resolution of the General Assembl...

Phenomenology is a unity of principles and methods for investigating the essence of phenomena. This article is a brief review of a series of works carried out by the authors over the past ten years. The general thrust of the works is that phenomenological ideas of physics are used to analyze earthquakes. A perfect model of phenomenological theory i...

The physics of earthquakes was contriubuted to by the concept of proper time of the source of a strong earthquake, which is different from universal (calendar) time. The earlier idea of proper time was implicit and has been considered only in relation to the physics of aftershocks. The present paper extends the applicability of the concept of prope...

After the main shock of an earthquake, a stream of aftershocks that does not subside for a long time is usually observed. Fusakichi Omori found that the frequency of aftershocks decreases hyperbolically with time. It has recently been observed that Omori's law can be viewed as a solution to a differential equation describing the evolution of afters...

One hundred years ago, Fusakichi Omori died. Our paper is dedicated to his memory. Omori made an outstanding contribution to the physics of earthquakes. In 1894 he formulated the law of aftershock evolution. Omori's Law states that after the main shock of an earthquake, the frequency of aftershocks decreases hyperbolically with time. In this paper,...

This paper is the first in a series of studies generalizing the Map of Expected Earthquakes (MEE) medium-term earthquake forecast method and analyzing the prospects for its further improvement. Over the past 35 years, the MEE method has been used in seismically active regions around the world with different tectonic conditions and seismic regimes....

This paper proposes phenomenological equations that describe various aspects of aftershock evolution: elementary master equation, logistic equation, stochastic equation, and nonlinear diffusion equation. The elementary master equation is a first-order differential equation with a quadratic term. It is completely equivalent to Omori’s law. The equat...

Данная статья является первой из серии статей, посвященных обобщению результатов применения метода среднесрочного прогноза землетрясений КОЗ (Карта ожидаемых землетрясений), перспективам и направлениям его дальнейшей модернизации. За последние 35 лет метод КОЗ был использован в сейсмоактивных районах мира, различных по своим тектоническим условиям...

The article “Comparative Analysis of the Methods for Estimating the Magnitude of Completeness of Earthquake Catalogs”, written by V.A. Pavlenko and A.D. Zavyalov, was originally published electronically in Springer-Link on 11 February 2022 without Open Access. After publication in volume 58, issue 1, pages 89–105 the authors decided to make the art...

The magnitude of completeness Mc of the earthquakes above which 100% of events are thought to be reliably detected is a vital parameter characterizing the completeness of seismic data. A known fact is that to obtain correct estimates of the parameters of seismicity, it is compulsory to take into account Mc variations in space and time. In this work...

Omori Law describes the evolution of the aftershocks of a strong earthquake. Established at the end of the century before last, it is characterized by the beauty of its form, quite definite clarity, as a result of which it still attracts considerable attention of the geophysical community. In recent years, we have accumulated considerable experienc...

The time dependences of the fracture concentration parameter characterizing the process of accumulation of defects formed in loaded objects, i.e., steel specimens in laboratory experiments and in the source zone of a strong earthquake, are obtained. When structural steel specimens are under tension, the fracture concentration parameter is estimated...

Recently, the physics of aftershocks has been enriched by three new problems. We will conditionally call them dynamic, inverse, and morphological problems. Dynamic problem is to search for the cumulative effect of a round-the-world seismic echo appearing after the main shock of earthquake. According to the theory, a converging surface seismic wave...

The Omori Law, which describes the repeated underground shocks after a strong earthquake, is written in the form of a nonlinear differential equation. An idea of the focal deactivation coefficient after the main shock is introduced. Two advantages of the new wording of the Omori Law are given. Firstly, there is an interesting possibility to natural...

The article describes the stages and results of research for developing a prototype of general seismic zoning maps of the Russian Federation (GSZ-2016). The standard GSZ-2015 and GSZ-2016 maps are compared. The need to transition to seismic hazard mapping of the Russian Federation in parameters of physical characteristics is shown. The global exper...

The deformation behavior of metals and rocks is analyzed. The stages of damage accumulation, the formation of deformation localization zones, the length distributions of the number of microcracks in metallic samples and faults in Earth’s crust, and the time dependences of acoustic emission and seismic events before the fracture of specimens and ear...

The damage and fracture criteria proposed to describe the damage accumulation processes in metallic specimens, rocks, and Earth’s crust during earthquake preparation are considered. The efficiency of application of these criteria for an analysis of damage on various scale levels is shown. The transition of fracture from one hierarchical level to an...

The outstanding Japanese seismologist Fusakichi Omori was born 150 years ago, on October 30, 1868. He discovered his first law in earthquake physics that now bears his name when he was 26. Essentially, Omori’s law tells us that the decay of aftershock rate follows a hyperbolic law. This paper provides a brief account of how that discovery was made....

This paper is devoted to the memory of the outstanding Japanese scientist. In 1896, Fusakichi Omori discovered the law of the aftershocks evolution that bears his name. We represent the Omori law in the form of a differential equation. This allows us to take into account the non-stationarity of rocks in the earthquake source, which "cools down" aft...

Based on the observation data for hundreds of the main shocks and thousands of aftershocks, the existence of effect of round-the-world surface seismic waves is demonstrated (let us conditionally refer to them as a round-the-world seismic echo) and the manifestations of this effect in the dynamics of the repeated shocks of strong earthquakes are ana...

Previously, we predicted and then observed in practice the property of aftershocks which consists in the statistically regular clustering of events in time during the first hours after the main shock. The characteristic quasi-period of clustering is three hours. This property is associated with the cumulative action of the surface waves converging...

On May 24, 2013, vibrations of the earth’s surface, caused by a strong earthquake, whose hypocenter was in the Sea of Okhotsk near the western coast of Kamchatka at a depth of 600 km, were recorded in Moscow and in a number of satellite cities. For Moscow, which has more than once felt the echoes of strong Carpathian earthquakes from the Vrancea zo...

ESC community held a PostHyogo consultation by using a questionnaire prepared by ESC Executive Committee (ExeCom) in 2014. Six questions were posed to the ESC community, asking for additional comments not specifically included within the questions. The questions were: 1. What is the role of ESC at regional and international level for improving the...

The 9th International Workshop “Physics and Forecasting of Rock Destruction” was held in the Institute of the Earth’s Crust, SB RAS, in Irkutsk on 02–06 September 2013. The article reviews the main events of this scientific forum and briefly describes its discussion results concerning prediction / forecasting of dynamic destruction of rocks due to...

The aftershocks of the catastrophic Sumatra-Andaman earthquake of December 26, 2004 ( M = 9.0) are analyzed in the general context of the theory of critical phenomena. The analysis relies on the idea that, according to this theory, critical transitions have two key properties. The first is that the intensity of the fluctuations in a dynamical syste...

Analysis of the Sumatra-Andaman earthquake on 26.12.2004 (M = 9) has allowed us to identify two non- trivial properties of the dynamics of aftershocks. First, the strongest aftershock (M = 7.2) was likely triggered by the round-the-world seismic echo of the main shock. The idea is that the surface waves propagating outwards from the main shock retu...

The Map of Expected Earthquakes (MEE) algorithm was suggested in the mid-1980s by G.A. Sobolev, T.L. Chelidze, L.B. Slavina, and A.D. Zavyalov, the most active members of a special informal team called QCSA (Quick-Look Comparative Seismic Analysis). Over the last 30 years, the algorithm has been tested in a variety of seismically active regions all...

The seismic catalogues of 1967–2008 for the Bishkek geodynamical test site are analyzed for the purpose of studying the response of seismic activity to the electromagnetic sounding of the Earth’s crust during two series of field experiments with high-power controlled sources. The first series of the experiments, which were carried out in 1982–1990,...

В статье обсуждается сильнейшее японское землетрясение 11марта 2011 года (Тохоку-оки) и другие связанные с ним события (форшоки, цунами, афтершоки, геодинамические последствия, другие землетрясения в данной зоне). Рассказывается сейсмическая история региона. Рассматриваются проблемы краткосрочного прогноза сильных тектонических землетрясений и умен...

The 33rd General Assembly of the European Seismological Commission (ESC) will be held on 1924 August 2012 in Moscow, Russia.

Данная статья продолжает серию публикаций, начатых в 2009 году и посвященных наиболее опасным геофизическим явлениям. Она вводит в круг вопросов, связанных с вулканами и их опасными проявлениями. В ней изложены основные представления о строении вулканов, их типах, распределении по земному шару, разрушительном и созидательном воздействии на среду об...

Статья вводит в круг проблем, связанных с одной из геофизических опасностей — землетрясениями. В ней изложены основные представления о возникновении землетрясений и их распределении по земному шару. Приводится описание основных понятий и характеристик землетрясения: его очаг, энергия (магнитуда), интенсивность сейсмических колебаний, приносимый уще...

Данная статья является второй частью работы “Прогностические аномалии сейсмического режима”. В ней представлены первые результаты применения методов и алгоритмов выделения прогностических изменений в сейсмическом режиме перед рядом сильных землетрясений в районе Западных Гималаев. Делается вывод о необходимости создания однородного и представительн...

This paper presents results obtained in 1980–2002 from studies of various aspects of earthquake prediction in relation to the development of a method of mediumterm prediction from a set of criteria.

The evolution of the concepts of the concentration criterion of fracture of solids, proposed by Zhurkov, in connection with its use for forecasting strong seismic events in earthquake source physics is considered. The results of long-term testing of the seismogenic fracture density as an earthquake precursor are analyzed in various seismically acti...

Results of retrospective testing of the MEE (mapping expected earthquakes) algorithm on the basis of catalogued earthquakes in western Turkey for the period from 1975 to 2000 are presented. The MEE algorithm was shown to be most efficient with averaging grid cells of the size ΔSMEE = 75 × 75 km. The prognostic efficiency index JMEE is 2.44, 3.29, a...

Strong (ML ≥ 5.5) and moderate (5.0 ≤ ML < 5.5) earthquakes that occurred in Greece and adjacent areas from 1996 to 2002 are examined and compared with the map of expected earthquakes (MEE for the same period constructed and published in early 1997. Analysis of the seismicity monitoring results indicates that the MEE prognostic algorithm can be use...

The paper presents results of the 15-year testing of the MEE (Map of Expected Earthquakes) algorithm using a set of various precursors and intended for the medium-term prediction of strong, K greater than or equal to 12.5 (M greater than or equal to 5.5), earthquakes in various seismically active regions of the world. The average prediction effecti...

Gradual restriction of fracturing toward the plane of the future main rupture and its subsequent localization near this plane are qualitatively described by the avalanche unstable-fracturing model of earthquake precursors. Localization of fracturing was recorded in the laboratory during tests of rock specimens. A study of this effect during the pre...

The estimation of the seismically dangerous zones of Kamchatka a n d Greece for the nearest years is given in this report on the basis of joint application of MEE (Map of expected earthquakes) algorithm and of RTL prognostic parameter. MEE algorithm is based on the analysis of such precursors as b-value, density o f seismogenic faults, number of we...

Acoustic emission (AE) in rocks is studied as a model of natural seismicity. A special technique for rock loading has been used to help study the processes that control the development of AE during brittle deformation. This technique allows us to extend to hours fault growth which would normally occur very rapidly. In this way, the period of most i...

In this paper we evaluate the present state of the seismic regime in Southern California using the concentration parameter of seismogenic faults (K sf ,Sobolev andZavyalov, 1981). The purpose of this work is to identify potential sites for large earthquakes during the next five or ten years. The data for this study derived from the California Inst...

The effect of the random spatial distribution of earthquake-generating faults on the estimation of the failure concentration parameter is investigated. It is shown that on the assumption of a fractal distribution of faults the failure concentration parameter is a power function of the size of a space in which this parameter is estimated. The power...

The seismic process is modeled by acoustic emissions in rock samples. A special procedure of rock loading is used with the aim of revealing regularities of formation and evolution of the acoustic structure. The procedure augments the period of macrofracture development and thus makes possible a detailed examination of the stage of most intensive in...

The technique for compiling maps of expected earthquakes has been developed and tested retrospectively and in real time.The conditional probability of future earthquakes was calculated based on geotectonic data, geodetic measurements and spatio-temporal variations of such seismic parameters as density of seismogenic faults, slope of the recurrence...

This paper presents a study of the time-space behaviour of certain physical parameters, namely, the number of pulses of acoustic and seismic emission, the density of seismogenic ruptures, and the in laboratory, mine and field experiments during the preparation and development of dynamic events at different scales. The preparation stage before failu...

The parameter gamma of the magnitude-frequency relation is dependent on the mechanical properties of the Earth and on the stress acting in it. The stresses are locally variable as the result of movements along seismic and aseismic fractures.-from Authors

From analysis of the data from the Kamchatka catalog we make the following two conclusions: 1. The narrow range of Ksf (the concentration criterion for seismic faults) (5<=Ksf<=8) falls in close proximity to analogous K values calculated and experimentally determined for rocks and other materials (3<=Ksf<=5). This implies that the same process of c...