大地电性结构的分界处容易加剧管道腐蚀，穿过大地分界面的管道在分界点处受到的地磁暴致灾风险比较大，提出一种可用于评估输油气管道的地磁暴灾害风险自评价描述的算法。改进算法的帕金森矢量在定位大地分界面时比传统算法的帕金森矢量更加准确；在可以识别大地分界面的前提下，改进算法的帕金森矢量方位角会在分界面附近完成±180°到0°或0°到±180°的过渡变化，距离分界面越近，方位角越能够反映大地分界面的倾向，改进算法的帕金森矢量长度在分界点处达到最小值；相邻地块电导率差值、空中电流源频率以及大地分界面与测线方向的夹角等因素会影响改进算法帕金森矢量的分布特性；利用帕金森矢量的方位角图和长度图两个判据可以定位穿过分界面位置的管道，相邻大地分界面之间存在虚拟界面，需要分析排除。仿真结果表明了这些结论的正确性，对管道防护具有重要的指导意义。

Pipeline corrosion is easily aggravated at the boundary of the earth’s electrical structure. The pipeline passing through the earth interface is subject to greater risk of geomagnetic storm disaster at the demarcation point. The algorithm in this paper can be used to evaluate the self-evaluation description of geomagnetic storm disaster risk for oil and gas pipelines. This paper holds that the improved algorithm’s Parkinson vector is more accurate than the traditional algorithm’s Parkinson vector in locating the geodetic interface. On the premise that the earth’s interface can be identified，the azimuth of the improved algorithm’s Parkinson vector will change from ±180°to 0° or 0°to ±180°near the interface, and the closer to the interface, the azimuth can better reflect the inclination of the earth interface, and the length reaches the minimum value at the boundary point. Factors such as conductivity difference between adjacent plots, the frequency of current sources and the angle between the earth’s interface and the line direction will affect the distribution characteristics of the improved algorithm’s Parkinson vector. The azimuth map and length map can be used to locate the pipeline through the interface position. There is a virtual interface between adjacent earth’s interfaces, which needs analysis and exclusion. The simulation results show that these conclusions are correct and have important guiding significance for pipeline protection.