A time-domain electromagnetic survey of the East Rift Zone, Kilauea Volcano, Hawaii

Abstract

A time-domain electromagnetic survey was conducted over the East Rift Zone of Kilauea Volcano, Hawaii. The purpose of the survey was two-fold. First, the survey was intended to give greater insight into interpretation techniques of time-domain electromagnetic data. Secondly, a more complete picture of the geologic structure and hydrology of the Rift, with special emphasis on its geothermal potential, was to be gained. To interpret the time-domain electromagnetic data, first the maximum-received voltages were converted to apparent resistivities and mapped. Next, the received transients were matched with a catalog of asymptotic curves. Then, theoretical layered-earth curves were calculated and the transients were again matched. Finally, use of a least-squares-fit computer program gave a more exact interpretation. Although the asymptotic curves have been calculated for no more than a three-layer case, the theoretical matching technique may be expanded to a greater number of layers.