NATURAL MAGNETIC ARCHIVES OF PAST GLOBAL CHANGE

Rock magnetic parameters of sediments reflect palaeoenvironmental and palaeoclimatic conditions during deposition in the marine and in the c ontinental realm. The processes which lead to enhancement or degradati on of the magnetic properties are well known - though not completely u nderstood. They include variable terrigenous material influx, organic and inorganic in situ formation of ferromagnetic minerals and diagenet ic destruction of these minerals. Cyclical changes in the magnetic min eral assemblages occurring at the orbital periodicities involved in st andard Milankovitch theory have been observed in numerous sedimentary records, at least during the last seven million years. This confirms t he relationship between rock magnetism and past global change. Quantit ative interpretation of the magnetic signals, however, is still in its infancy and is hampered by the complex interplay of the signal format ion processes.