1887

Abstract

Measurement of the vertical gradient (pseudo-gradient) of the magnetic field instead of total field measurement is one of the most popular methods in performing the high-accurate magnetic surveys especially when the noise level is very high. The process of transformation of the measured pseudo-gradient field into the total field is associated with the problem of the reconstruction of the long-wave field constituent. The common way in solving this problem is to add some small number of measurements of the total field T. Further processing of the survey results almost always includes the separation of the anomalous field into the constituents, associated with the distinct groups of sources. The traditional method in solving of formulated problems is the spectral operator application [e.g. C. Fechant, D. Orseau and N Florsch, 1998]. According to our experience spectral methods are not accurate enough and it could lead to the appearance of the false anomalies. These effects are due to the inaccurate Fourie series summation and edge effects (Gibbs effect). Following the ideas of V. Aronov (1963) and A. Bjerhammar (1964) we suggest an alternative method based on the simultaneous approximation of the measured values of the pseudo-gradient and the total field values by the model field of the equivalent dipole sources system. This algorithm allows us to calculate any magnetic field transformations, interpolation of the field values and to separate field into constituents. Let N be the number of the pseudogradient measurements (Gi) and M - the number of total field measurements Tj. N>M; i=1,..,N; j=N+1,..,N+M. We approximate these measurements by the system of K≤ N+M dipoles situated at some points (xk, yk, zk), k=1,..,K, in the lower half-space. In general magnetic moments of the dipoles mk can be determined from the following minimum condition:

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201406375
1999-09-06
2020-07-09
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201406375
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error