HR: 0830h
AN: NS41A-06    [Abstracts]
TI: Recent Geophysical Investigations in Iceland
AU: * Horsley, T J
EM: T.Horsley@Bradford.ac.uk
AF: Department of Archaeological Sciences, University of Bradford, Bradford, BD7 1DP United Kingdom
AU: Schmidt, A
EM: A.Schmidt@Bradford.ac.uk
AF: Department of Archaeological Sciences, University of Bradford, Bradford, BD7 1DP United Kingdom
AU: Dockrill, S J
EM: S.J.Dockrill@Bradford.ac.uk
AF: Department of Archaeological Sciences, University of Bradford, Bradford, BD7 1DP United Kingdom
AB: Interest in the archaeology of the North Atlantic region has grown considerably over the last two decades but until very recently the application of geophysical methods had remained limited to a few isolated investigations. This poster presents results from a program of research to assess the potential of established archaeological prospection techniques in Iceland: an area that presents new archaeological contexts and natural environmental conditions. Throughout many parts of the world magnetic survey methods are the most widely employed geophysical techniques for the location and characterization of archaeological sites. However, they are often considered to be of little value over igneous bedrocks due to their intense thermoremanent magnetization. This poses a challenge in Iceland where 90% of the geology is igneous. In addition to basaltic lavas there are numerous glacial deposits, sandur plains and volcanic tephra layers. Electrical methods have long been used in archaeological investigations to accurately plan structural remains, however such features also present a problem in Iceland. The lack of good building stone and timber resulted in turf being the dominant building material from the Viking settlement in about 871AD until the beginning of the 20th century. High-resolution surveys have been undertaken at 40 sites across Iceland using the Geoscan Research FM36 fluxgate gradiometer (0.5m x 0.25m) and RM15 earth resistance meter (0.5m x 0.5m). The results presented here demonstrate that whilst the intense geological anomalies often dominate the magnetometer data, overwhelming more subtle anomalies due to pits and ditches, it is possible to identify areas of activity as clusters of magnetic bipoles due to near-surface rocks from archaeological contexts. Furthermore, turf remains and compacted floor layers have also been successfully identified in earth resistance surveys. Combining the results from these two complementary methods aid in the distinction between natural and anthropogenic sources and often allows accurate identification of archaeological features. Despite the limiting factors, this work demonstrates the potential of these techniques for archaeological prospection in Iceland and throughout the North Atlantic, especially when undertaken as part of an integrated approach.
DE: 1540 Rock and mineral magnetism
DE: 1803 Anthropogenic effects
DE: 8499 General or miscellaneous
DE: 9315 Arctic region
SC: Near-Surface Geophysics [NS]
MN: 2005 Joint Assembly