In 2003 NordWest Ltd carried out array AMT studies at the Khatat ground of the Mirny kimberlite field (western Yakutia). The works were customized by Alrosa Company. The works were purposed at estimation of AMT technique efficiency in pipe exploration. Over the target region, a series of tufa explosion pipes associated with the fault Central'ny zone had been revealed earlier.
AMT results are shown in maps of apparent resistivity, polar diagrams and real induction arrows. In the apparent resistivity maps at frequencies 10, 100, 1000 and 5000 Hz, regions of decreased resistivities are apparent, which coincide with the location of the explosion pipes detected earlier.
The maps of amplitude polar diagrams revealed a typical pattern of radial orientation of major axes of diagrams relative to the center of the apparent resistivity anomaly. It is notable that just above the very center of the anomaly the shapes of diagrams are isometric. Such a pattern can likely be considered as a criterion indicative of a pipe.
In the map of real induction arrows at 1 kHz superimposed on the map of determinant apparent resistivity, a set pattern of arrows orientation outsides the pipe is seen.
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