Extended Data Fig. 8: Orthogonal NRM demagnetization diagrams of some representative specimens and their respective normalized intensity decay plots: a) D1AX1, b) E1BX2, c) C2CX1, d) E4C3X.
![Extended Data Fig. 8](https://cdn.statically.io/img/media.springernature.com/full/springer-static/esm/art%3A10.1038%2Fs41586-024-07467-0/MediaObjects/41586_2024_7467_Fig11_ESM.jpg)
Solid/open symbols in orthogonal diagrams correspond to the vector endpoints’ projections onto the horizontal/vertical plane. These specimens mainly contain thermally altered substrate, although (d) may include traces of ash. NRM values are normalized by the estimation of specimens’ mass excluding plaster content. Steps below 200 °C were disregarded to avoid any viscous influence.