Results 161 to 170 of about 3,946 (197)

Foreshock cavities and internal foreshock boundaries

Planetary and Space Science, 2011
Abstract We present two case studies of cluster encounters with foreshock cavities. For one event, we are able, for the first time, to accurately relate the observation of a foreshock cavity to the measured position of the bow shock. This allows us to compute the shock angle, a vital parameter in models of foreshock cavity formation, with greater ...
Laurence Billingham, Steven J. Schwartz, Mark Wilber   +2 more
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Statistical model of earthquake foreshocks

Physical Review A, 1992
We propose a statistical model of rupture as a mechanism for the occasionally observed marked increase of seismic activity prior to a great earthquake. The physical ingredients of the model are those of geometrical inhomogeneity and viscoelastic creep.
, Sornette, , Vanneste, , Knopoff
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Foreshock compressional boundary

Journal of Geophysical Research: Space Physics, 2009
We employ 2.5‐D electromagnetic, hybrid simulations that treat ions kinetically via particle‐in‐cell methods and electrons as a massless fluid to study the formation and properties of a newly discovered boundary named the foreshock compressional boundary (FCB).
N. Omidi, D. G. Sibeck, X. Blanco‐Cano
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A study of ULF wave foreshock morphology—I: ULF foreshock boundary

Planetary and Space Science, 1992
Abstract We have used ISEE 1 and 2 magnetometer data to determine the forward boundary of the upstream ULF wave foreshock. We first examine the presence and absence of ULF waves immediately upstream from the bow shock. The statistical results show that the ULF foreshock starts at θBn ∼ 50° on the bow shock, and fills the entire upstream region ...
G. Le, C.T. Russell
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Foreshocks and earthquake prediction

Tectonophysics, 1972
Abstract If a group of foreshocks can be distinguished from ordinary seismic activities, it would contribute to earthquake prediction. In the case of two Japanese earthquakes, which were preceded by immediate foreshocks, the coefficient “b” in the magnitude versus frequency equation was significantly smaller than that of the aftershocks or of the ...
Shigeji Suyehiro, Hiroshi Sekiya
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The electron foreshock

Advances in Space Research, 1995
An overview of the observations of backstreaming electrons in the foreshock and the mechanisms that have been proposed to explain their properties will be presented. A primary characteristic of observed foreshock electrons is that their velocity distributions are spatially structured in a systematic way depending on distance from the magnetic field ...
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MMS observations of wave activity in the particle foreshock bubble foreshock region

2020
<p>Foreshock bubbles (FBs) are kinetic transient phenomena formed due to the interaction between IMF discontinuities and backstreaming energetic ions in Earth’s foreshock region. FBs can be driven by both rotational discontinuities and tangential discontinuities and are typically observed under higher solar wind ...
Mengmeng Wang, Quanqi Shi
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Foreshocks of strong earthquakes

Izvestiya, Physics of the Solid Earth, 2014
The specific enhancement of ultra-low-frequency (ULF) electromagnetic oscillations a few hours prior to the strong earthquakes, which was previously mentioned in the literature, motivated us to search for the distinctive features of the mechanical (foreshock) activity of the Earth’s crust in the epicentral zones of the future earthquakes. Activation of
A. V. Guglielmi, L. E. Sobisevich, A. L. Sobisevich, I. P. Lavrov   +3 more
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The spatial density of foreshocks

Geophysical Research Letters, 2011
exaly   +2 more sources

Foreshocks and earthquake prediction

Tectonophysics, 1975
Abstract Results of a statistical investigation of the magnitude and time distributions of foreshocks in the area of Greece are reported. Further evidence is presented that the parameter b , in the frequency—magnitude relation, has a smaller value before than after the main shock, and that the time distribution of foreshocks follows a statistical ...
openaire   +1 more source