Modeling shallow self-potential anomalies over electronic conductors

Abstract

Field measurements of self-potential indicate that anomalies may be divided in a shallow anomaly and a deep anomaly. This paper presents a new understanding of the current flow causing SP-anomalies, and how this can be modeled by using the analogy between magnetic flux density lines and electric current lines. Mathematical models are presented for shallow SP-anomalies. Several older models may be applied for the deep part of the anomaly. The new model is applied for interpretation of an SP-anomaly from the KTB drilling site in Oberpfalz in Germany. The deep part was interpreted using a plate model which has been known for years. The final curves of the measured anomaly and the calculated curves for the shallow part and the deep part of the anomaly are presented.