helicopter-borne electromagnetic (hem) is a fast and high resolution airborne electromagnetic (aem) method that is frequently used for imaging of the subsurface resistivity structures. this is a versatile and cost effective method, frequently has used in mineral and groundwater exploration and various environmental problems. modern frequency-domain hem systems utilize small electromagnetic, mag...

Defined by international telecommunications union (ITU), the spectrum in the band between 30 and 300 Hz are named as super low frequency (SLF). In this band, the electromagnetic waves are rarely shielded by strata of lower resistivity and can spread strongly. Therefore, it can be used on the earth’s surface to detect goaves underground. The equipment, which use the natural SLF electromagnetic s...

There is growing interest in marine direct current (DC) resistivity methods for sub-seafloor exploration of a broad range of geophysical and geological targets. To address this, we have developed a new marine DC method with a vertical electrode configuration (VEC). Compared to conventional marine DC methods that use a horizontal electrode configuration, the shape and position of our VEC cable c...

The aim of the present study was to analyse electric resistivity at different ambient temperatures between 300 to 20K in the frog sciatic nerve and salmon sperm DNA. When the electrical contacts were leaned just into the sciatic nerve, an increase of the sciatic nerve resistivity was observed for 240 K < T < 300 K and a rise of electrical conductivity was apparent below 240 K. This dependence i...

We present original apparent resistivity records for stations located in the Chinese provinces of Hebei and Sichuan, along with seismicity patterns, fault maps, and limited hydrologic data. These records are part of a 30-year dalabase of geoelectric signals t_ha__t have been recorded in China by a nationwide network of more than 100 stations et up by the State Seismological Bureau of the People...

In this study we describe and compare photometric and resistivity measurement methodologies to determine solute concentrations in porous media flow tank experiments. The first method is the photometric method, which directly relates digitally measured intensities of a tracer dye to concentrations without previously converting 5 the intensities to optical densities. This enables an effective pro...

The paper presents the results of factor analysis multi-electrode geoelectric data measured in area Surány aquifer. 9-variable dataset on first profile was examined by using 2, 3, 4 and 5 factors. calculations show that Factor 1 carries effects IP (Induced Polarization), while 2 shows effect apparent resistivity (Rho) with greatest weight. In weight current (In) is largest. Based all this, it c...