A complex of geophysical and geoelectrochemical methods for diagnostics of corrosion danger of gas pipelines is offered. On the basis of complex geophysical and geoelectrochemical information it is possible to solve the following problems: high-precision determination of the location and depth of the gas pipeline; detection of places and degree of violations of insulating coating of gas pipelines, accompanying metal corrosion damage; evaluation of attenuation factor of variable component of cathodic protection currents; determination of cathodic protection potential in places of gas pipeline insulation damage; identification of corrosion dangerous areas and evaluation of corrosion hazard of pipelines. The relative contrast of geoelectrochemical anomalies characterizes the duration and intensity of corrosion. The suggested methodology complements the existing methods of gas pipelines condition diagnostics. New method was tested at gas pipelines of Lentransgaz enterprise in 1999-2000. According to the results of complex researches the areas of gas pipelines isolation coating violation were marked with indication of places of corrosion damages of pipelines.
