NanoPaleoMagnetism

After a number of adventures, our new Lakeshore/PMC AGM-VSM system is finally up and running! We are proud to present our very first FORC diagram, measured on a shard of fire obsidian from Glass Buttes, Oregon, using the AGM configuration. This material was chosen on the basis of previous electron microscopy work by Ma et al. (2007) that showed particles of pure magnetite with sizes just inside the pseudo single domain (PSD) range. This is confirmed by the FORC diagram, which shows classic PSD features! This is an extremely weak sample, magnetically, so this image demonstrates not only the high sensitivity of the AGM but also the excellent new VARIFORC (Egli, 2013) smoothing option of FORCinel v. 2.0.