This study provides an evaluation of spectral responses of hollow ways in Upper Mesopotamia. Hollow ways were used for the transportation of animals, carts, and other moving agents for centuries. The aim is to show how the success of spectral indices varies in describing topologically simple features even in a seemingly homogeneous geographic unit. The variation is further highlighted under the changing precipitation regime. The methodology begins with an exploration of the relationship between the date of a multispectral scene and the visibility of hollow ways. The next step is to evaluate the impact of rainfall levels on numerous indices and to quantify spectral contrast. The contrast between a hollow way and its background is evaluated with Welch’s t-test and the association between precipitation regime and spectral responses of hollow ways are investigated with Correspondence Analysis and Fisher’s test. Results highlight an intrinsic relationship between the precipitation regime and the ways in which archaeological features reflects and/or emits electromagnetic energy. Next, the categorization of spectral indices based on different rainfall levels can be used as a guidance in future studies. Finally, the study suggests contrast becomes an even more fruitful concept as one moves from the spatial domain to the spectral domain.
Archaeological geophysics is a range of techniques for the minimally invasive, remote investigation of the physical parameters of the near-surface environment. This suite of methods is complementary to archaeological survey or excavation as it can provide information about the stratigraphy of the survey area, locate anthropogenic traces of the past, document their spatial dimensions and—under ideal conditions—explore the physical properties of subsurface materials. Both material culture items such as a building foundations and indirect indications of anthropogenic activity such as subsurface disturbance or evidence of burning are excellent direct targets for geophysical investigations since they can be differentiated on the basis of their material properties from the wider soil context. In addition to directly locating archaeological material, geophysical techniques can make an important contribution to geoarchaeological investigations by elucidating the site stratigraphy and mapping its lateral geometry. In some cases, such as when locating prehistoric material buried offshore or within open Palaeolithic sites, the reconstruction of past landscapes may make a more important contribution to archaeological investigations than the direct geophysical detection of archaeological materials. Different material culture items have characteristic physical properties (such as electrical resistance or conductivity, magnetic susceptibility) and so require different instrumentation for effective detection. The main techniques for archaeological prospection include magnetometer, resistance meter, magnetic susceptibility meter, ground-penetrating radar and electromagnetic induction meter. Apart from that, seismic methods (reflection and refraction seismics), gamma spectroscopy and gravity techniques are also used in certain circumstances. Unfortunately, there is no standard approach for the application of one specific geophysical method for all archaeological materials in all geological environments. The success of geophysical prospection techniques depends on a combination of soil and sediment characteristics as well as depth below surface and preservation of archaeological findings. In order to achieve the most reliable results and enhance the chance of detecting archaeological material, an integrated, multi-method approach is suggested. In addition to field surveying, the effective processing of measured geophysical data is a crucial part of the interpretation process. Data processing aims to enhance signals of interest in order to better delineate archaeological and geological features. It helps to produce more interpretable results and therefore facilitates and fosters collaboration between geophysicists and archaeologists.
The South Caucasus has been largely absent in broader discussions of prehistoric population aggregation in Greater Eurasia. The authors use remote sensing, surface collection and magnetometry to investigate two hilltop fortress settlements at the margins of the Kura River Basin, with a particular emphasis on satellite settlements around the main hills. The results support a model of settlement growth in which previously mobile groups settled around the fortress, while maintaining a degree of spatial and social separation. The use of multiple survey techniques reveals a complex picture of settlement organisation, with implications for comparative analysis of prehistoric population aggregation models.
The IGEAN (Innovative Geophysical Approaches for the study of Early Agricultural villages of Neolithic) Thessaly project focused on Early and Neolithic settlements in Thessaly, Central Greece. The aim of the project was to highlight in an extensive way differences in settlement layouts while investigating commonalities as a way to understand Neolithic use of space. To accomplish this, a suite of geophysical prospection techniques (geomagnetic, electromagnetic induction, and Ground Penetrating Radar (GPR)), aerial platforms (historic aerial imagery and Remotely Piloted Aerial Systems (RPAS)) as well as very high resolution spaceborne sensors were integrated to acquire comprehensive pictures of settlements. Results of the IGEAN project provide archaeological information on the dynamic character of enclosures, the structure of architectural features and open spaces within sites as an indication of economic or communal spaces. At the same time, they demonstrated the importance of employing a suite of different geophysical techniques to reveal different aspects of the hindered prehistoric settlements that could not be highlighted with a single geophysical approach.
Multi-sensor prospecting is a fast-emerging paradigm in archaeological geophysics. Given suitable ground conditions for navigation, sensor arrays drastically increase efficiency in data collection. In particular, geomagnetic prospecting benefits from this development. Despite these advancements, data processing still lacks a best-practice approach. Conventional processing methods developed for gridded data has been challenged by sensor arrays “roaming” in the landscape. In realization of the issue, the Innovative Geophysical Approaches for the Study of Early Agricultural Villages of Neolithic Thessaly (IGEAN) Project explored various innovative techniques for the betterment of the multi-sensor geomagnetic data processing. As a result, a modular pipeline is produced with minimal user intervention. In addition to standard steps, such as data clipping, various other algorithms have been introduced. This pipeline is tested over 20 Neolithic settlements in Thessaly, Greece, three of which are presented here in detail. The proposed workflow provides drastic improvements over raw data. As a result of these improvements, the IGEAN project revealed astonishing details on architectural elements, settlement enclosures, and paleolandscapes, changing completely the existing perspective of the Neolithic habitation in Thessaly.