| Popis: |
Impressed Current Cathodic Protection (ICCP) systems are extensively used for the protection of central Europe‘s dense network of oil-, gas- and water pipelines against destruction by electrochemical corrosion. Protection is provided by the injection of a DC current into the pipeline (Figure 2). However, occasional pipeline integrity surveys demand the protection current to be switched on- and off periodically. The resulting time varying pipe current induces secondary electric- and magnetic fields in the surrounding earth. While these fields are usually considered to be unwanted cultural noise, we aim at utilizing these fields for EM exploration, since the switching cycles typical fundamental periods roughly correspond to periods used in controlled source EM applications (CSEM). |
