Magnetic characterization of ferrichromite in soils developed on serpentinites under temperate climate

作者：Horen H^*; Soubrand M; Kierczak J; Joussein E; Neel C

来源：Geoderma, 2014, 235: 83-89.

DOI：10.1016/j.geoderma.2014.06.026

• Serpentinites
• Magnetic properties
• Ferrichromite
• Iron chromium spinels
• Soil
• Temperate climate
• Alteration

The objective of this study is to characterize alteration processes of iron chromium spinels in soils developed on serpentinites using their magnetic properties. Three pedons developed on serpentinites from two European Hercynian massifs were considered. Two soils from the central Massif (France) are formed under mild and humid climate, the third soil is located under colder and dryer climate zone (Szklary Massif - south western Poland). The most of magnetic carriers of serpentinites belong to the iron chromium spinel group. These minerals have been characterized by studying rock and soil magnetic parameters i.e. magnetic susceptibility and low field thermomagnetic behavior. Chemical composition of soils and rocks was investigated by ICP-MS and ICP-AES. The nature of magnetic minerals and the geochemical behavior of iron and chromium in soils depend on hydrothermal and/or metamorphic previous alteration of the parent rocks. The presence of zoned ferrichromite is related to dissociate behaviors of iron and chromium during pedogenesis. In both soil profiles from France the pedogenic alteration of magnetic carriers is limited to a slight conversion of magnetites to maghemites in the upper horizons. In Polish soil developed under colder and dryer conditions, the magnetic minerals remain unaltered even in topsoil horizon.

• 出版日期2014-12