Magnetic Resonance in the Subsurface – 5th International ... - LIAG

One-Dimensional Theoretical Research on MRS Excited by Finite Current Wire
One-Dimensional Theoretical Research on MRS Excited by Finite Current
Wire
Yuanjie Li, Zhenyu Li, Jianwei Pan, Jiagang Zhang, Hao Liu, Kai Wang
Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan, PRC
liyuanjie305@163.com
Magnetic Resonance Sounding, abbreviated as
MRS, is a novel geophysical technic specially
designed for direct water exploration by using
NMR phenomena. At present, in the fields a
large loop normally acts as both transmitter
and receiver, and in this model information of
aquifers in varied depth from the shallow to the
deep will be obtained through amplifying
stimulating pulse. However, this traditional
work mode has shortcomings of intense labour
of the operator, great influence from landform,
only one-dimensional information of aquifers
being achieved, and finite maximum depth of
investigation which is a problem to be solved
urgently. These drawbacks may be related to
field source that is the magnetic field of the
loop, so, we propose a pioneering and bold
assumption that the stimulating loop is
superseded by finite current wire as the field
source. In theory, the new mode possesses few
advantages of flexible lay-pattern, free from
tomography limitation, affluent information
about underground aquifer, potential research
in detecting depth. Therefore, we will do
research about MRS methods excited by finite
current wire, and determine its feasibility.
The distributing of magnetic field stimulated
by finite current line is numerical simulated in
the homogeneous half-space, while its
characteristics will be quantitatively analysed.
And then various aquifers models in the mode
of MRS method excited by wire source will be
built to acquire NMR signals, characteristics of
which will be compared with those in the
traditional mode. By doing so ,it is can be
concluded that it is feasible to employ line
source exciting MRS technique , and also the
superiority of this new method over
conventional mode can be demonstrated. To
perfect one-dimensional theoretical system of
MRS method stimulated by line source,
appropriate inversion about new method will
be carried out.
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Magnetic Resonance in the Subsurface – 5 th International Workshop on Magnetic Resonance
Hannover, Germany, 25 – 27 September 2012
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