As a member of the Editorial Board of Geoarchaeology, I have had the pleasure of organizing this special issue of the journal. Magnetic studies have long played an important role in archaeology. Traditionally, these studies fall into two areas: magnetic prospection and archaeomagnetism (both secular variation and archaeomagnetic dating). According to one way of dividing up the archaeological sciences, these traditional magnetic applications are examples of geophysical surveys for location, and of dating studies.
The importance of site formation processes is one of the themes of this journal. These processes are often studied via more classical geoarchaeological methods of sedimentology, stratigraphy, and geomorphology, as well as geochemical and biological archaeometric methods. Magnetic studies can also yield insight into site formation processes in diverse ways, including applications not included in the traditional types of magnetic studies. In particular, the developing fields of environmental magnetism and rock magnetism have much to offer archaeology in terms of new methods, concepts, and applications. The articles in this issue serve to illustrate those linkages.
The geographic scale of interest of these papers ranges from the regional landscape to the lateral/vertical extent of the archaeological site to the individual artifact. Magnetic methods are used to examine: cultural land use practices at Cahokia Mounds (Dalan and Banerjee); natural sediment sources in the Shangqui archaeological region, China (Jing and Rapp); climatic effects on sediment magnetic properties in Portugal (Ellwood et. al.); and provenience of lithic materials and technological treatment of those artifacts during manufacture (Borradalle et. al.). Thus both natural and cultural transformations of the magneto-archaeological record are addressed. It is important to consider these magnetic transformations because they do not necessarily correspond to visible changes on a macroscopic scale.
A second special issue of Geoarchaeology with additional applications of magnetism to site formation processes is currently in the works.