Quantitative analysis of self-potential anomalies: Review of case studies from various SP applications

Abstract

Self-potential (SP) method is one of the most non-expensive and unsophisticated geophysical methods. However, its application limits absence of reliable interpreting methodology, first for the complex geological-environmental conditions. The typical disturbances appearing in the SP method are discussed. To exclude these noise components before the quantitative analysis, some ways for their removing (elimination) are presented. Some brief review of the available interpretation methods is presented. For the magnetic method of geophysical prospecting, special quantitative procedures applicable under complex physical-geological environments (oblique polarization, uneven terrain relief and unknown level of the normal field), have been recently developed. Earlier detected common peculiarities between the magnetic and SP fields have been extended. These common aspects make it possible to apply the advanced procedures developed in magnetic prospecting to SP method. Besides the reliable determination of the depth of anomalous targets, these methodologies enable to calculate the corrections for non-horizontal SP observations and direction of polarization vector. For classification of SP-anomalies is proposed to use a new parameter – 'self-potential moment'. These quantitative procedures (improved modifications of characteristic point, tangent techniques and areal method) have been successfully tested on SP models and employed in real situations in mining, archaeological, environmental and technogenic geophysics. The obtained results indicate practical importance of the developed methodologies.