## 3 Results
### Magnetic Susceptibility of Some Construction Materials for Pavilions
#### 3.1.1 Magnetic Susceptibility Determinations

Table 2: Anomalous geomagnetic effects observed near the concrete bases of initially built pillars at the Klimovskaya observatory. Figure 2: The White Sea observatory magnetometer pavilion: (**a**) General view of the building; (**b**) Interior; (**c**) The vector Overhauser magnetometer POS-4 installed in the pavilion. The polyethylene tube appeared to be non-magnetic (0 SI). For the concrete mix, the filler and the glue, the magnetic susceptibility measurements were carried out first directly on the materials (the kappameter was simply applied to the packages). Next, samples of each material (except for asphalt shingle (onduline) supplied in a large sheet) were taken in plastic cups for magnetic susceptibility measurements in a smaller volume. Then, 4-5 measurements were made for each material, after which the magnetic susceptibility of the samples in plastic cups was determined. When determining the magnetic susceptibility on samples with a cylindrical surface (for example, on a core), corrections must be introduced because the values on a cylindrical surface are lower than on a plane [17]. Since a plastic cup with a volume of 200 g is a cone and its diameter at one end is larger than at the other, for convenience, it was decided to choose an average correction factor from the PIMV kappameter operation manual (p. 5) for diameters corresponding to the filled part of the cup. Therefore, a coefficient of 1.4 was chosen. The measured \(\kappa\) values were multiplied by the mentioned correction factor. In Table 3, the column \"\(\kappa\), \(\times 10^{-5}\) SI units, l.v.\" contains the measurements on packing bags, and in the column \"\(\kappa\), \(\times 10^{-5}\) SI units, s.v.\" there are measurements of selected samples in plastic cups (\"l.v.\" and \"s.v.\" are \"large volume\" and \"small volume\", respectively). The correction factor is 1.4. Multiplying by it the values of the magnetic susceptibility determined for the samples, we obtain values generally close to those obtained on the bags (see the column \"Total \(\kappa\), \(\times 10^{-5}\) SI units\". Thus, we made sure of the purity of the experiment. According to the results of measurements, glue (0 SI units), as well as sand concrete (9.45 \(\times\) 10\({}^{-5}\) SI units), were classified as very weakly magnetized materials. Expanded clay was weakly magnetized (127-143 \(\times\) 10\({}^{-5}\) SI units). The reason may lie in the technology of its production. However, it can still be used in the footing as a filler because it will be far from the magnetometer. The only material which had a relatively high magnetization was asphalt shingle (234-363 \(\times\) 10\({}^{-5}\) SI units, i.e., weak to medium magnetization according to the classification Table 1). Probably the asphalt shingle was contaminated by some ferromagnetic particles during its manufacturing process. Another experience in magnetic susceptibility studies was related to the installation and development of the Gyulagarak observatory [1], IAGA code GLK, located in Armenia, in collaboration with the A. Nazarov Institute of Geophysics and Engineering Seismology of the National Academy of Sciences of the Republic of Armenia (IGES NAS RA). It was