Nuclear magnetic resonance as a tool for hydrogeologists

in #hydrogeology7 years ago (edited)

Hello steemit,

I'm going to show a part of my geophysical water exploration work, called Nuclear magnetic resonance as a tool for hydrogeologists.

The surface Nuclear Magnetic Resonance method (SNMR) is a new application of Nuclear Magnetic Resonance (NMR) for groundwater investigation. It is already an established method, but still, much of the problems involved in this method requires further research effort. The encouragement of geophysicists and hydrologists to use this method in their development necessitate a good understanding of SNMR by a broad community of scientists across different disciplines.

Principleples of the method.

The operating principle of the method consists of the excitation of the hydrogen protons contained in the groundwater which are in the presence of the Earth’s magnetic field.

The magnetic moment vector of the hydrogen protons in the vacuum are randomly oriented, since they are located in the presence of the earth’s magnetic field, the hydrogen protons are oriented parallel to the magnetization vector of the Earth’s magnetic field. The method of nuclear magnetic resonance is based on the application of three physical phases:

Natural equilibrium:

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At the equilibrium, water molecules are oriented towards the magnetic North.

Waves transmission:

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Waves transmitted at a specific frequency excite the water molecules.

  1. Signal reception:

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When the waves are stopped, the water transmits a magnetic signal recorded on the surface, during the come back to equilibrium.

The great thing about this method is that it allows to directly discriminate the presence of the aquifer through the response produced by the hydrogen atoms. Where the electric potential difference in function of time
is characterized by the emission of electromagnetic waves from the relaxation of atoms.

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References:

Legchenko, A., (2013) “Magnetic Resonance Imaging for Groundwater”. Orléanse: Willey.
Pérez, I., (2017). “Estudio Hidrogeológico mediante sondeos eléctricos y resonancia magnética nuclear en el sector La Mata, Edo. Miranda.”. Universidad Simon Bolivar, p 8