Geoscience Reference
In-Depth Information
1 Introduction
Earthquake is the trembling or shaking movement of the earth's surface. It occurs
when energy stored within the earth, usually in the form of strain in rocks, sud-
denly releases. This energy is transmitted to the surface by seismic waves. Most
earthquakes are minor tremors. Larger earthquakes usually begin with tremors, but
rapidly take the form of one or more violent shocks, and end in vibrations of
gradually diminishing force called aftershocks.
The emergence of high quality measurement devices from a decade ago had
directed the courses of earth-related efforts towards providing better and more
accurate knowledge of the mechanical and chemical ongoing in the earth during
natural phenomena. Laboratory micro-scale experiments, powerful sensors, and
advance imaging devices allow scientists to present detailed explanations of
possible atomic and molecular interactions in materials. With the satellites
research organizations that could send their sensors to high altitudes producing
round-the-clock monitoring of the earth's surface and atmosphere in wide scales,
there is long list of image and non-image datasets proposing a wide array of views
from any part of our globe. In this climate, theoreticians are able to base their
theories about the origins and mechanisms of natural events upon encompassing,
more accurate inspections of what is going on under, on, and above the earth's
surface.
During the past years, occurring numerous devastating earthquakes in different
parts of the world that caused thousands of deaths and millions of dollars in property
loss and impacts on strategic and scientific planning has stirred a lot of interest among
researchers to work on the identification and detection of the earthquake precursory
events to propose possible short-term prediction models that lead to mitigate damage
from future earthquakes (Ryabinin et al. 2011 ). So far, they have identified some
events that theoretically are expected to take place and practically are possible to
detect before and during earthquakes. Studies on the surface and air temperature,
surface latent heat flux, relative humidity, radon isotopes, ionosphere variations and
some other precursors resulted in successful detection of extraordinary changes
during several past oceanic and land earthquake instances and assumptions on the
causes of these events observed during seismic activities (Wang and Shi 1984 ; Gorny
et al. 1988 ; Nosov 1998 ; Freund and Ouzounov 2001 ; Tronin et al. 2002 , 2004 ; Dey
and Singh 2003a , b ; Cervone et al. 2004 , 2006 ; Pulinets 2004 ; Saraf and Choudhury
2003 - 2005a , b , c ; Saraf et al. 2008 ; Choudhury et al. 2006 ; Parrot et al. 2006 ; Pulinets
et al. 2006 ; Singh et al. 2006 , Singh et al. 2007a , b , 2010 ; Qin et al. 2009 ; Kumar et al.
2009 ; Revathi et al. 2011 ; Alvan et al. 2012 ).
In this chapter we will look at heat based events on and above surface prior to
and during main shakes (known as earthquake precursors) which can be monitored
from space as well as the possibility of detecting warning foreshocks and move-
ments of the earth's ground from seismograph.
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