The objective of this primer is to provide an introduction into the why, what and how of timelapse electrical geophysics.
This primer is targeted at non geophysicists who have an interest in what timelapse electrical geophysics is and whether it possibly could help them in their efforts. This can include hydrologists, remediation professionals, agricultural scientists, water resource professionals, and in general anyone who wants to know what is happening in the subsurface and is interested in finding about timelapse electrical geophysics. No prerequisites should be needed to understand the material discussed in this primer.
This primer was motivated by the growing number of non geophysicists who are interested in using timelapse electrical geophysics (also known as 4D electrical resistivity, 4D ERT and time-lapse resistivity) and who want to gain an understanding of this technology.
Based on personal experience (and on experience from colleagues) we realized that it is easy to get confused about what timelapse electrical geophysics can (and cannot) do. While timelapse electrical geophysics is discussed in multiple publications we are not aware of one place which provided an introductory level overview of this technology. This motivated Subsurface Insights to assemble this primer. This primer does not pretend to be comprehensive, but it hopefully should provide a good entry point for those interested in learning more about this technology.
Readers are encouraged to provide feedback on this primer (either positive or negative) so that we can clarify parts which are unclear and possibly enhance certain areas which are not sufficiently covered.
The primer is divided in several sections. The contents of these sections are provided here.