Frequency domain electromagnetic induction (FDEM, often simply abbreviated EMI) is a geophysical technique that enables sensing the bulk electrical conductivity of the subsurface, contactless over large areas. The development of multi-coil and multi-frequency electromagnetic induction instruments (EMI) has facilitated the recovery of the likely subsurface electrical conductivity through an inversion procedure. EMagPy is an open-source software that has been designed for processing EMI data and inverting for layered 1D models, possibly with 2D or 3D constraints. The code is written in Python and provides an application programming interface (API) to use, for instance, in Jupyter Notebook and a tabbed graphical user interface similar to its sister code ResIPy. EMagPy can also generate synthetic measurements from a given subsurface model and then invert them again to see how much of the initial model can be recovered. In this workshop, we will demonstrate how to use EMagPy GUI and API for field data processing and synthetic modeling.
Paul McLachlan studied Geology at Edinburgh University before pursuing a PhD in hydrogeophysics with Lancaster University/British Geological Survey. Among the tools used, frequency-domain electromagnetic induction was well suited for the rough terrain of the wetlands he studied. During his PhD, Paul contributed to the open-source geophysical codes ResIPy and EMagPy. After his PhD he taught hydrology in China and was postdoctoral researcher at Bordeaux University using geophysics in vineyards. He is currently a researcher at Aarhus University, where he focuses on transient EM methods in water scarce regions.
Guillaume Blanchy studied bio-engineering at Liege University (Belgium) and then did a PhD at Lancaster University/Rothamsted Research (UK) on geophysical methods to monitor root water uptake of different wheat varieties. Among them, frequency-domain electromagnetic induction was well suited for measurements during crop growth on large fields due to its high throughput and non-invasiveness. Guillaume contributed to open-source software EMagPy and ResIPy during his PhD. After a year of postdoctoral research at the Flemish Research Institute for Food and Fisheries (ILVO), Guillaume is now a researcher at Liege University, where he studies the effect of controlled drainage on saline/freshwater interface dynamics in the Flemish polders using geophysics.