OHM DETECT
An OHM DETECT survey delivers basic resistivity results in geologically simple environments. It is a cost-efficient option when there is little ambiguity in the resistivity structure of the subsurface.
Even in the most simple survey environment, pre-survey modelling with source waveform design is critical to the success of Controlled Source Electromagnetic Imaging (CSEMI).
The interpretation of an OHM DETECT survey is typically limited to normalised anomaly versus offset curves. In a very well constrained resistivity environment, such interpretation can have value. However with the use of JEM: Joint EM, OHM can provide intuitive depth specific images. Such images locate resistive features, for example, hydrocarbons and volcanic sills. JEM jointly inverts both the source generated electric field and the naturally occuring electromagnetic field data to provide an improved 2D resistivity depth section.