Heavy mineral weathering under acidic soil conditions
Abstract
The weathering of heavy minerals in acid soil profles (pH 4±5) has been studied in terms of their
relative mineral proportions and by using the surface etching features of apatite and hornblende
grains. An increasing stability order of: apatite, titanite, hornblende, garnet, epidote, zircon is
found in the 45±63 mm coarse-silt fraction of soils developed on tills in southwestern Sweden. In
glaciofluvial deposits, sorting processes during deposition have largely determined the variations
in heavy mineral content of soils, and only the dissolution of apatite is signifcant. Hornblende
etching is more extensive in soils with low hornblende content, indicating that the release of
cations relative to the amount of hornblende is greater in such soils.