Results are presented from studies oftelluric currents on two pipelines in Canada: the Norman Wells-Zama pipeline in northern Canada, and the North Bay-Morrisburg pipeline in southern Canada. On each pipeline
simultaneous recordings were made of pipe-to-soil potentials at different points along the pipe. These observations showed simultaneous fluctuations, at all sites, that coincided with variations of the geomagnetic
and geo-electric fields. Tests of the relation between the variations at different sites showed a high correlation at nearby sites and a decrease in correlation at sites more than 100 km apart. This is consistent with the fact that geomagnetic disturbances in Canada are predominantly due to currents in the ionosphere 100 km above the earth's surface.
Keywords: telluric currents, pipeline modeling, geomagnetic disturbance