Яндекс.Метрика

N.O. Kozhevnikov, E.Y. Antonov, Y.K. Kamnev, V.V. Olenchenko, A.E. Plotnikov, S.M. Stefanenko, A.N. Shein

Выпуск: 11 , Том: 55 , Год издания: 2014
Сериальное издание: Russian Geology and Geophysics
Страницы: 1333-1339

Аннотация

The effect the metal casing of a vertical borehole may exert on transient electromagnetic (TEM) responses has been studied in a field experiment. Eddy currents in the casing affect transients only slightly at early times, but the casing effect predominates at late times. Therefore, early-time TEM response measured near a borehole can provide information on shallow subsurface. The late-time TEM signals induced by the eddy currents in the casing show exponential behavior b ъexp(- t /t). The time constant t refers to the rate of eddy current decay in the casing; the amplitude b
индекс в базе ИАЦ: 046828