Determining the influence of soil layers on apparent soil resistivity through small-scale laboratory experiments

Electrical resistivity (ER) method, non-destructive approach determining subsurface anomalies by leveraging electrical properties. In-situ ER is popular owing to its quick, reliable and continuous subsurface data, although heterogeneity across horizontal and vertical orientation is less explored. In this regard, present study tends to understand this effect by carrying out small-scale laboratory ER tests focusing on how varying vertical soil layer positions impact resistivity. Two distinct soil types with varying resistivity were arranged in both perpendicular and parallel direction to current flow, where low and high resistive layers were placed adjacent to one another. Results derived from study indicated that placement of low resistive soil before high resistive one leads to 37.58 % reduction in resistivity. Furthermore, parallel alignment resulted in 9.89 % decrease compared to perpendicular layering. Thus, these findings tends to highlight significance of layering in influencing resistivity values and underscoring the complexity of electrical resistivity testing.