ENVIRONMENTAL MAGNETISM - AN INTRODUCTION

In environmental magnetism, the properties of magnetic minerals are us ed as proxy parameters for many purposes. Examples are paleoclimate an alysis, paleoceanographic studies, provenance studies of sediments, st udies of anthropogenically-induced pollution, and archeological invest igations. Mineral-magnetic techniques are sensitive, require little sa mple preparation, are rapid, often grain-size indicative, and usually non-destructive. These techniques involve 'bulk' properties which make s them complementary to geochemical micro-analytical techniques. Measu rements include the field-and temperature-dependence of various types of induced and remanent magnetizations. Mineral-magnetic methods are c ontinuously being improved. The underlying causal relations between ob served mineral-magnetic properties and the processes that led to those properties, are becoming increasingly better understood, and the exte nded use of such properties as proxy parameters for many processes is foreseen. The following environmental magnetic applications are review ed: the analysis of paleoclimatic variations in loess and other sedime nt types, the untangling of sedimentary features in piston cores, and the interpretation of the anthropogenic impact on the environment, in archeological studies and in studies of present-day pollution. The pat hway between the provenance area and depositional site is shown to hav e a crucial impact on the magnetic properties.