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PRESENTING BY
P.EPAPRA
M150146CE
GROUNDWATER CHEMISTRY CHANGES BEFORE EARTHQUAKES
EARTHQUAKE
An Earthquake is the sudden shaking of the earth surface.
May 1, 2023 2
Effects Rupture
Death
Building collapse
Effects Fires Liquefaction Landslides
Hazardous effects of Earthquakes
1. Loss of life and property2. Floods3. Tsunami 4. Landslides
Can we predict Earthquakes?
May 1, 2023 8
Pre-Earthquake signalsUnusual behaviour of animals
Low to ultra-low frequency electromagnetic emissions.
Perturbations in the Ionosphere
Changes in the atmosphere near the ground
Changes in Ground or Springwater chemistry
Contents:1. Rocks-Sources of Electric chargers
2. Positive Holes and Peroxy defects
3. Oxidation of water to hydrogen peroxide
4. Closure of Rock Battery in the field
5. Other reactions at Rock-Water interface
6. Unusual animal behaviour
7. Disturbances in Ionosphere
8. Discussions
9. Conclusions
10. References
Rocks-sources of electric currents
Due to tectonic stresses in the earths crust, highly mobile
electronic charge carriers are activated.
These charge carriers can flow out, spreading fast and far.
This process is called ELECTRIFICATION of Rocks
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STRESSED ROCK-EXPERIMENT
• Loaded at one end
• 1.2 m long granite slab fitted with cu electrode at both ends.
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STRESSED ROCK-EXPERIMENT
• Two types of charge carriers are appeared in the stress rock volume.
• They are hole (h•) and an electron (e’).
• As (h•) spread into unstressed rock, the stressed sub volume becomes negatively charged. ROCK BATTERY
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Luminous phenomena-Reason Due to very rapid
increase of the stresses, more of the charge carriers are activated than can be dissipated.
They burst out of the earth surface causing an electrical discharge and luminous phenomena.
Points we need to know…• Where do the charge carriers come from?
• What is the nature of the stress-activated holes?
• How long to they live before recombining?
• Why are they able to flow through unstressed rock?
May 1, 2023 15
Peroxy defects and Positive Holes
• Essentially all rocks in the earth’s crust contain ubiquitous defects.
• They are in active in normal conditions.
• In silicate minerals they consist of peroxy links i.e. normal bonds between [SiO4] structural units are replaced by .
• These peroxy bonds will momentarily break when rocks are subjected to mechanical stress.
Positive hole activation
Flow of Positive Holes• In order for a positive hole to travel from left to right, a succession of electrons has to hop from right to left.
•This mechanism is called as phonon-assisted electron hopping mechanism.
Oxidation of Water to Hydrogen Peroxide• Upon arriving at rock water interface Positive hole oxidises Water
molecule.
• The O- subtracts an H from H2O it changes into an OH- and this
OH- gets imbedded into Rock surface.
Contd…..• Two •OH radicals combine to form hydrogen peroxide:
O–surface + H2Osolution OH-
solution +•OH solution
•OH solution + •OH solution H2O2 SOLUTION
Closure of Rock Battery in the field• Nature provides alternatives to close the Rock Battery.
• Possible by establishing a electrolytically conductive pathway.
• After forming H2O2 Solution at rock water interface current continues
through the water by way of H3O+.
2 e’ + 2 H3O+ 2H2O + H2
• The closure of the battery is possible by electrolyzing water to H2O2 and
H2O
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Contd..
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Electro-corrosion of Rocks
• 20x6 Cm2 Cu electrode.
• Load of 10 Tons at the centre.
• 1 Cm of water.Slab of Gabbro 30x60x9 Cm3
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Excess cation concentrations measured in water bath.
Other reactions at Rock- Water interface
• Other oxidation reactions involving organic compounds of
biogenic origin dissolved in spring and groundwater.
• Example:1
• M 7.6 Izmit earthquake of August 17, 1999.
• Significant changes in the intensities of the fluorescence
spectra of water.
May 1, 2023 25
Fluorescence spectra of water samples (1999-2003)
July 10, 1999, 7 weeks before
October 6, 1993 about 7 weeks after
After one year
Contd…•Example : 2
• M5.3 Earthquake on Nov.24,2004,Lago di Garda,Italy.
• Focal depth- 25km, 8km from the village of Salo.
• Here also changes were observed in florescence
spectra.
May 1, 2023 27
Fluorescence spectra of water samples
1-REFERENCE
2, 3, 4-OPEN OUTLETS
5- FOUNTAIN ON THE ROAD
6-ADJACENT CREEK
May 1, 2023 28
Unusual animal behaviour
Recent example of unusual animal behaviour
• M6.3 L’Aquilla earthquake on April 6, 2009, Italy.
•Activity of common Toads at a breeding site in a small lake, 75km
north of L’Aquilla, Italy declined dramatically 5 days before
earthquake.
• Highly unusual in these amphibians.
• Once breeding is started they do not leave the site for 3-7 weeks
until spawning is completed.
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Observations(Mar 26-Apr-17), 2009NO OF MALE TOADS OBSERVED RAINFALL RECORDS
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Contd…
• The ground was highly saturated in the week prior to earthquake.
• Such conditions would be advantageous to toads which always
prefer to be in humid environments.
• The disappearance of toads from breeding site is highly unusual.
May 1, 2023 32
Disturbances in the Ionosphere These disturbances consist of changes in the transmission
characteristics of radio waves between two stations.
The processes that occur on the Earth surface before
Earthquakes has influence on the conc. of free electrons in the
Ionosphere.
These electrons contribute to reflection of radio waves and
make them to be transmitted over longer distances.
Evidence for ionospheric disturbances Radio signals emitted from two stations in Italy, ICV in Sardinia and ITS in
Silicy and received by MOS station in Moscow.
On the way to MOS station these radio waves pass over the Ionosphere
region that lies in the influence of the L’Aquilla earthquake.
Discussion Many of the pre- earthquake signals phenomena can be
perceived by animals eliciting unusual behaviour.
But such reports have widely been called anecdotal.
But toads behaviour before L’Aquilla Earthquake is an exception.
It was part of a systematic 4-year study of toad breeding
behaviour at this very location.
Contd…. At the rock-water interface the h• oxidizes H2O to H2O2 and will oxidize organic
compounds dissolved in spring water from earth prone areas.
Effects of these changes on biological systems:
•Time and dose dependant toxic effects of Hydrogen peroxide on lipids in the cell
membrane.
• Hydroxyl radicals are highly reactive and damaging.
• Inactivates important enzymes required for biological functioning.
Contd… The combined evidence provided by toads observation and
ionospheric disturbances suggests that toads were able to
perceive some pre-seismic cues in their environment.
As h• spread out from the most severely stressed rock volume
deep below, they cause different secondary processes at the land
surface and at the rock-water interface.
The process at rock-water surface consists of changes in lake
water chemistry.
The process at land surface consists of ionosphere disturbances.
CONCLUSIONS The possible common mechanism for diverse physical pre-earthquake processes and
incidents of anomalous animal behaviour were discussed.
Observing the results we can confidently say that the chemistry changes in the
groundwater before earthquakes are connected to earthquakes.
Making use of this information and conducting further experiments in all earthquake
prone places around the world we can forecast earthquake risk.
If the results are observe to be same we will have a way to alert people to an impending
disaster
May 1, 2023 38
References 1. Rachel A.Grant ,Tim Halliday, Groundwater Chemisrty changes before major
earthquakes and possible effects on animals; Int. J.Environ. Res. Public Health 2011.
2. Freund, F.T. Toward a unified solid state theory for pre-earthquake signals. Acta
Geophysics. 2010.
3. Freund, F.T. Pre-earthquake signals – Part I: Deviatoric stresses turn rocks into a
source of electric currents. Natural hazards and Earth Science Systems, 2007
May 1, 2023 39