Local geomagnetic field variations of external origin: A case study of Armenia

Grigorian, A. G.

doi:10.1134/s1069351307060109

Cited by 5 publications

(2 citation statements)

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“…О по вышении проводимости этих зон перед сильными зем летрясениями известно из данных МТЗ. Наблюдалось последовательное изменение проводимости среды от верхней мантии к нижней коре (по данным монито ринга вариаций геомагнитного поля на сети магнито вариационных станций) в период подготовки Спитак ского землетрясения [Grigorian, 2007]. Анализ прово дился на периодах магнитных возмущений 5-20 мин (глубина контроля 2-10 км), 30-60 мин (глубина кон троля 10-20 км) и S q вариациях (период 5-20 часов, глубина контроля 100-300 км).…”

Section: верхняя мантияunclassified

Subvertical congestions of the earthquake hypocenters -- seismic "nails"

Vadkovsky¹

2012

Vestn. Otd. nauk Zemle

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Formation of the geological medium boundaries and patterns is specific, but such specific features have not been fully considered yet. No consideration is given to the nature of periodic variations of various parameters of the geological medium from the surface to the depth of the upper mantle. Remarkable are properties of interblock/interplate marginal structures that ensure steady and quite contrasting movements of blocks, and it is of interest which processes provide for such properties. Another related question is why insignificant attention is still given to some variations of geophysical fields that might be interpreted as precursors of largescale fracturing? Degassing (first of all, hydrogen degassing), P-T parameters at any depth level, and pressure of the upper layers determine the crystalline structure of the medium, including layers between blocks. Due to combinations of these impacts, principally new conditions are established, in which amorphized/irregular and regular structures are formed. Such a twophase system, including a variable number of regular/crystalline and irregu lar/amorphized phases, may be responsible for specific and unique spatial geological structures, such as the Moho, blocks and 'subduction' zones, and variations of their parameters. The stable amorphized structure of the boundary interlayers facilitates sliding of blocks against each other, which does not permit any control of transfer of movements to rapid displacements fol lowed by strong earthquakes. This article considers the nature of processes that generate amorphized structures in the geo logical medium and geological consequences of such processes.Key words: lithosphere, upper mantle, medium structure, hydrogen degassing, amorphized structure, the Moho, subduction zone.Recommended by V.V.

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Section: верхняя мантияunclassified

Subvertical congestions of the earthquake hypocenters -- seismic "nails"

Vadkovsky¹

2012

Vestn. Otd. nauk Zemle

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“…Заметные изменения про водимости верхней мантии начались примерно за 2.5 года до события, а параметров нижней коры -с за держкой на один год. Здесь также рассматривали влияние на среду высокой скорости продвижения фронта «флюидизации» [Grigorian, 2007]. С действием эндогенной активности Земли необходимо рассматри вать зависимость числа землетрясений от географиче ской широты зоны мониторинга.…”

Section: о времени подготовки крупномасштабных разрывовunclassified

Why we cannot predict strong earthquakes in the Earth’s crust

Gufeld

Матвеева

Новоселов³

2011

Geodyn. Tectonophys.

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In the past decade, earthquake disasters caused multiple fatalities and significant economic losses and challenged the modern civilization. The wellknown achievements and growing power of civilization are backstrapped when facing the Nature. The question arises, what hinders solving a problem of earthquake prediction, while longterm and continuous seis mic monitoring systems are in place in many regions of the world. For instance, there was no forecast of the Japan Great Earthquake of March 11, 2011, despite the fact that monitoring conditions for its prediction were unique. Its focal zone was 100-200 km away from the monitoring network installed in the area of permanent seismic hazard, which is subject to non stop and longterm seismic monitoring. Lesson should be learned from our common fiasco in forecasting, taking into account research results obtained during the past 50-60 years.It is now evident that we failed to identify precursors of the earthquakes. Prior to the earthquake occurrence, the observed local anomalies of various fields reflected other processes that were mistakenly viewed as processes of preparation for large scale faulting. For many years, geotectonic situations were analyzed on the basis of the physics of destruction of laboratory specimens, which was applied to the lithospheric conditions. Many researchers realize that such an approach is inaccurate. Nonetheless, persistent attempts are being undertaken with application of modern computation to detect anomalies of various fields, which may be interpreted as earthquake precursors. In our opinion, such illusory intentions were smashed by the Great Japan Earthquake ( Figure 6). It is also obvious that sufficient attention has not been given yet to fundamental studies of seis mic processes. R e c e n t g e o d y n a m i c sThis review presents the authors' opinion concerning the origin of the seismic process and strong earthquakes, being part of the process. The authors realize that a wide discussion is needed to address the issues raised in this publication, including problems and possibilities of prediction of earthquakes in the crust.Incontrovertible achievements of the Earth sciences are reviewed, considering specific features of seismic events and variations of various parameters of the lithosphere, the block structure of the lithosphere and processes in the lithosphere. Much attention is given to analyses of driving forces of the seismotectonic process. The studies of variations of parameters of the medium, including rapid (hourly or daily) changes, show that processes, that predetermine the state of stresses or the en ergy capacity of the medium (Figures 2 and 3) in the lithosphere, are overlooked. Analyses are based on processes of interac tions between ascending flows of hydrogen and helium and the solid lithosphere. A consequence of such processes is gas porosity that controls many parameters of the medium and the oscillation regime of the threedimensional state of stresses of the block structures (Figures 6, 7, and 12), which impacts...

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Filtration effects: A new type of earthquake precursors

Kissin

2014

Dokl. Earth Sc.

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Local geomagnetic field variations of external origin: A case study of Armenia

Cited by 5 publications

References 0 publications

Subvertical congestions of the earthquake hypocenters -- seismic "nails"

Subvertical congestions of the earthquake hypocenters -- seismic "nails"

Why we cannot predict strong earthquakes in the Earth’s crust

Filtration effects: A new type of earthquake precursors

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