3-D Numerical Study on Controlled Source Electromagnetic Monitoring of Hydraulic Fracturing Fluid With the Effect of Steel-Cased Wells

A Feasibility Study of Land CSEM Surveys With a Near-Casing Source for Hydraulic Fracturing Monitoring

“…Therefore, when performing volume-weighted conductivity averaging, the weighted volumes of the four adjacent elements remained unchanged. The new relationship for average conductivity can be expressed as follows [11]:…”

“…However, the injection of fracturing fluid during hydraulic fracturing induces changes in the electrical properties of the formation, laying the geophysical groundwork for utilizing the CSEM method for hydraulic fracturing monitoring. It is worth noting that in hydraulic fracturing monitoring using the CSEM method, the substantial electrical conductivity contrast between underground steel casings and the formation leads to current diffusion across boreholes, significantly distorting the electromagnetic signals collected by the receivers [11]. Therefore, prior to employing the CSEM method for hydraulic fracturing monitoring, it is essential to use numerical simulation methods to study the EM response characteristics of steel casings.…”

Development and Consideration of 3D Transient Electromagnetic Forward Modelling for the Hydraulic Fracturing Monitoring

“…Therefore, considering the non-fracturing formation and high-conductivity casing as the background conductivity and using the EM signal difference value between two adjacent multi-stage fracturing processes, the EM signal variations of the fracturing formation are extracted. Hu et al (2022) proposed an efficient numerical approach to manage the discretion of well casings by assigning lumped conductive properties to the mesh edges.…”