2026-06-08T13:40:05Zhttps://docta.ucm.es/rest/oai/request
oai:docta.ucm.es:20.500.14352/245712023-08-26T17:07:18Zcom_20.500.14352_14col_20.500.14352_15
Docta Complutense author Guerrero Suárez, Sara author Martín Hernández, Fátima 2023-06-18T06:54:54Z 2023-06-18T06:54:54Z 2016-06 0956-540X 10.1093/gji/ggw134 https://hdl.handle.net/20.500.14352/24571 http://dx.doi.org/10.1093/gji/ggw134 http://gji.oxfordjournals.org/http://www.researchgate.net Several works have reported that haematite has non-linear initial susceptibility at room temperature, like pyrrhotite or titanomagnetite, but there is no explanation for the observed behaviours yet. This study sets out to determine which physical property (grain size, foreign cations content and domain walls displacements) controls the initial susceptibility. The performed measurements include microprobe analysis to determine magnetic phases different to haematite; initial susceptibility (300 K); hysteresis loops, SIRM and backfield curves at 77 and 300 K to calculate magnetic parameters and minor loops at 77 K, to analyse initial susceptibility and magnetization behaviours below Morin transition. The magnetic moment study at low temperature is completed with measurements of zero field cooled-field cooled and AC susceptibility in a range from 5 to 300 K. The minor loops show that the non-linearity of initial susceptibility is closely related to Barkhausen jumps. Because of initial magnetic susceptibility is controlled by domain structure it is difficult to establish a mathematical model to separate magnetic subfabrics in haematite-bearing rocks. spa Haematite natural crystals: non-linear initial susceptibility at low temperature journal article URL https://docta.ucm.es/bitstreams/6e1ba9be-01e8-426c-a5c2-47e5d492b20c/download File MD5 3e0a27b0587a64c63f22c4d72118ea49 1425607 application/pdf Martín-H,F 03 preprint.pdf URL https://docta.ucm.es/bitstreams/80e589e4-094f-42b6-b594-45a6d2921b17/download File MD5 ec6e1f708e55952128d010855f209dab 103889 text/plain Martín-H,F 03 preprint.pdf.txt