New information about the geoelectric structure of the Moscow syneclise, a vast tectonic structure within the craton, is obtained at Profile IV in the framework of the Rifey Programme. The profile comprises 162 MT sites; its length is 790 km.
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Apparent in the resistivity cross-section, based on the drilling and seismic prospecting data, are the Mid-Russian aulacogen that forms a basement depression, and the allied uplift in the sediments. Due to the presence of a resistive layer (screen) not permeable for transverse electric current, this uplift clearly manifests itself in the transverse impedance. At the same time the longitudinal impedance "illuminates" the rock mass section beneath the screen and thus makes it possible to reveal the target Devon, Vend, and Rifey rocks perspective for oil and gas. The thickness of these rocks within the Soligalych aulacogen is estimated as 2-3 km, and the resistivity amounting up to a few Ohm·m may speak for the possibility of rocks being good reservoirs.
Highly resistive complex at the bottom of the section dated as Archean-Lower Proterozoic consists of large blocks having different resistivities. At the boundaries of the Moscow syneclise this complex is represented by presumably Archean rocks. In the central part of the Moscow syneclise the basement proved higher conductive, seemingly due to the presence of Early Proterozoic rocks.