Isothermal remanence experiments at room and at liquid nitrogen temperature: Application to soil studies

A simple magnetic mineral identification technique is proposed which measur es isothermal remanent magnetisation (IRM) acquired in different field stre ngths at 293 K and 77 K. Magnetic parameters are introduced that use these IRMs in order to distinguish concentration and type of ferromagnetic minera ls in different magnetic states. The method determines easily contributions of superparamagnetic ferrimagnetic minerals in environmental magnetism stu dies. In addition, high coercivity goethite and possibly superparamagnetic hematite are identified. The analysis of the magnetic properties of a soil profile on a Late Pleistocene terrace from the Jarama river in central Spai n is given as an example.