A new prototype of fast-heating oven dedicated to roc magnetism investigations – FUReMAG

The new equipment we are developing will be able to precisely apply the paleo/archeo-intensity determinations protocol proposed by Dekkers & Bohnel (EPSL, 2006) and Fabian and Leonhardt (EPSL, 2010).

The prototype is being assembled.

Once the final prototype will be achieved, it will be tested on different types of samples by our national and international partners.

This new type of oven was patented:
Patent No. 1256194 filed June 28, 2012 and extended by the University of Montpellier until 2014.

This project is a significant development of a project submitted last year that was not funded. It focuses on the developing of a new type of oven dedicated to rock magnetism experiments. This instrument will be included in the chain of data acquisition to observe the past behavior of the Earth's magnetic field. Hence, this is a new geophysics-oriented equipment. Two key points determine its characteristics. The first is to heat uniformly a rock sample of a 10-cc-standard volume as fast as possible. The second is to apply to the sample during the heating (and the cooling) a precise magnetic induction field, perfectly controlled in 3D. This latter feature is lacking in traditional ovens used in labs: the magnetic induction field can be applied only along a single direction, which is usually imposed by the geometry of the furnaces. The new generation of oven that we propose to develop have three direct applications. The first is certainly the most important. Recent developments on the methodology for documenting the intensity of the ancient Earth magnetic field, as recorded in rocks or archaeological artifacts, allow to use samples which until now were not measured because their magnetic properties do not meet selection criteria required by conventional methods. However, these new experimental protocols require that samples be heated and cooled under a field parallel to its natural remanent magnetization (NRM). Currently, no oven does match this constraint. Yet, such new measurement protocols would possibly double the number of data currently available. The second concerns the anisotropy of thermo-remanent magnetization (TRM). Baked clay artifacts, such as pottery, tiles and bricks, are often characterized by a strong magnetic anisotropy, mainly connected to their manufacture procedures. When these materials are used to reconstruct the recent history of the Earth's magnetic field, this anisotropy must be taken into account for reliable measurements. On this point, the new type of oven presented in this project would achieve a greater accuracy in estimating this parameter as the one obtained with current experimental devices. The third focuses on methodological and theoretical developments. The team of rock magnetism in Montpellier has worked extensively in this area. This new equipment certainly will open new perspectives. The design of the prototype and the preliminary calculations are completed. A preliminary version of the prototype allowed to perform preliminary tests. The project funding covers the assembly of the final prototype, the quality tests that require a national and international expertise, and the phase of dissemination, exploitation of results, and seeking industrial partners to commercialize this new experimental device.