%0 Journal Article
%T Preliminary Results of Marine Electromagnetic Sounding with a Powerful, Remote Source in Kola Bay off the Barents Sea
%A Valery Grigoryev
%A Sergey Korotaev
%A Mikhail Kruglyakov
%A Darya Orekhova
%A Yury Scshors
%A Evgeniy Tereshchenko
%A Pavel Tereshchenko
%A Igor Trofimov
%J International Journal of Geophysics
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/160915
%X We present an experiment conducted in Kola Bay off the Barents Sea in which new, six-component electromagnetic seafloor receivers were tested. Signals from a powerful, remote super-long wave (SLW) transmitter at several frequencies on the order of tens Hz were recorded at the six sites along a profile across Kola Bay. In spite of the fact that, for technical reasons, not all the components were successfully recorded at every site, the quality of the experimental data was quite satisfactory. The experiment resulted in the successful simulation of an electromagnetic field by the integral equation method. An initial geoelectric model reflecting the main features of the regional geology produced field values that differed greatly from the experimental ones. However, step-by-step modification of the original model considerably improved the fit of the fields. Thereby specific features of the regional geology, in particular the fault tectonics, were able to be corrected. These preliminary results open the possibility of inverse problem solving with more reliable geological conclusions. 1. Introduction Recently marine electromagnetic methods have become a valuable tool for seafloor mapping (e.g., [1, 2]). Among them, methods based on the natural (magnetotelluric) field offer advantages over those based on controlled source electromagnetic methods (CSEM) for lower-crust and upper-mantle mapping, while the latter offer advantages for upper-crust mapping. Although in general terms the audiomagnetotelluric method has been successfully applied to upper-crust survey too, such is not the case for the auroral zone, where the necessary plane-wave condition is roughly violated. A number of types of seafloor electromagnetic receivers measuring four (horizontal electric and magnetic) or five (the same plus vertical magnetic) components of the field, with various types of control sources dropped into the sea have been implemented ([3¨C8]). However, it is known that measurement of the sixth component (vertical electric) can be of much interest, because it is particularly sensitive to the insulating crust structures ([9]). On the other hand, it can be advantageous to use the powerful stationary control source for land mapping (e.g., [10]) and it is hoped that employment of such a powerful land-based source will also be beneficial in shelf mapping. In this paper, we present the experiment that made this possibility a reality. The first six-component electromagnetic seafloor receivers have been tested in Kola Bay off the Barents Sea. Signals from a distant, powerful super-long
%U http://www.hindawi.com/journals/ijge/2013/160915/