The MIMATOM project set out to develop Micro-Magnetic Tomography (MMT), a new method for extracting reliable records of the Earth’s magnetic field from volcanic rocks. This required solving several technical challenges: building and calibrating a Quantum Diamond Microscope (QDM), obtaining high-resolution 3D reconstructions using micro-CT, linking these datasets accurately, increasing the reliability of magnetic moment determinations, and making the computations efficient enough to analyze thousands of grains. All of these goals were successfully achieved. A dedicated QDM laboratory was established at Utrecht University and is now fully operational. High-resolution micro-CT imaging was obtained through the European EXCITE network. New computational routines now allow thousands of grain moments to be reconstructed in minutes rather than days, and a statistical framework identifies which grains reliably record the magnetic field while excluding those that do not.
With the method established, MMT was applied to geological case studies where conventional paleomagnetic approaches had yielded ambiguous results. These included Devonian pillow lavas, Ediacaran volcanic dykes (in collaboration with the University of Oslo), and Archaean dykes from Greenland. These applications showed that reliable magnetic information can be recovered selectively from individual grains, producing clearer reconstructions of the past magnetic field. In the final phase of the project, we demonstrated that, under favorable conditions, the internal magnetic domain structure of single grains can be inferred from their stray magnetic fields. This was enabled through collaboration with QZabre (Zurich), and it opens new research directions and forms the conceptual basis of the PI’s subsequent research proposals. The results of MIMATOM have been disseminated through peer-reviewed publications, conference presentations, workshops, and the organization of the 18th Castle Meeting on Paleomagnetism in Utrecht. The computational tools are openly available, and the QDM laboratory will remain in operation at Utrecht University, accessible to external researchers, ensuring continued development and use of the method beyond the project timeframe.
