Two Iron-Age Settlement Sites in Germany: From Field Work via Numerical Modeling towards an Improved Interpretation

Abstract

Geophysical exploration of archaeological sites has been a successful tool becoming more and more popular in the last decades. Many archaeological features can be detected with magnetic gradiometry (MGR), such as fire places, burned loam, metal artifacts, or other remnants, which produce a remanent magnetic signal detectable on the surface. However, as magnetic minerals are also present in natural settings, e.g. sedimentary and magmatic rocks and sediments derived from these host rocks, the MGR signal from archaeological artifacts is often embedded in a broader geomorphological signal, which makes separation of the different sources difficult. We provide geophysical data from two complex archaeological sites in northern Germany, which have been obtained with different methods, e.g. magnetic gradiometry (MGR), electrical resistivity tomography (ERT), electro-magnetic mapping (EM), and ground-penetrating radar (GPR). The combination of geophysical methods maps different material properties of both the geomorphological and the archaeological sources. We then use the three-dimensional modeling tool PREDICTOR to analyze the sources for the geophysical signals, e.g. the dominant signal in Leimbach, resulting from infill of palaeo-channels in the settlement area, and fire places as well as shafts in the hill fort of Lossow. The model prediction enables us to quantify the structures in the sub-surface and therefore helps to unravel complex situations often present in archaeological excavations.

Three‐dimensional modelling of a pre‐Aksumite settlement at the archaeological site of Seglamen, Aksum, northern Ethiopia using integrated geophysical techniques

“…Field procedures for the magnetic prospection method have been refined considerably in the last two decades. Currently, the use of magnetic gradiometer and microcomputer‐controlled automatic data collection systems have enabled low‐noise and high‐productivity surveys (Clark, ; Gaffney, Gater, Linford, Gaffney, & White, ; Kaufmann et al, ; Shaaban et al, ). However, the available model MP2 proton precession magnetometer (Scintrex) was used to acquire the total field magnetic data with the aim of outlining the spatial distribution of intra‐site magnetic anomalies of potential archaeological significance.…”

“…This method has been used to map buried stone foundations and soil features such as ditches, pits, trenches, etc. as this may maintain contact or interface between domains of different susceptibility and to outline the locations of strongly magnetized structures such as forges, kilns, hearths, and campfire sites as these acquire stronger magnetization from burning (Kaufmann, Ullrich, & Hoelzmann, 2015;Leucci et al, 2015;Tsokas & Hansen, 2000). Recent advance in technology has allowed the acquisition of large databases and more precise evaluation of field data (Ansari & Alamdar, 2009;Li & Oldenburg, 1996).…”