The Ajvide/Remote Sensing Project (swedish version)
Ajvide, Eksta Parish, Gotland, Sweden
The study of prehistoric economies, settlement patterns, social organisation and cultural change requires comprehensive data from large-scale archaeological field investigations. The necessity of localizing all existing remains of settlements, graves and other prehistoric activities within an area, with the aim to reconstruct seasonal movements or hunting strategies, for example, emphasizes the need and use of advanced prospecting methods for the localization of sub-surface remains together with the more traditional inventory procedures. These methods of remote sensing can be roughly divided into three main groups: airborne photography and satellite imagery, geophysical and digital methods and phosphate surveys. Furthermore, sampling, test excavations and topographical analyses for the reconstruction of the paleolandscape of large regions is requisite in order to make possible a coherent reconstruction of the scattered prehistoric remains that are visible above ground.
Infrared colour photograph of the Ajvide site with surroundings, Eksta Parish, Gotland. The c. 200 000 square meter large dwelling site and grave field can be seen just right of the middle part of the picture as a lighter piece of land stretching out in the ancient lagoon, about 4700 years ago, when the coastline was about 12 meters higher than today.
In much the same way, high demands must be put on advanced documentation at archaeological investigations. No interpretation or reconstruction of any prehistoric activity can be better than the documentation on which it is based. Since an overwhelming majority of our interpretations of archaeological materials are based on the documentation of excavations carried out several decades ago, or even earlier, it is not surprising that modern, large-scale excavations often fundamentally change existing theories concerning prehistoric ways of life. The need of new, far-reaching and interdisciplinary archaeological investigations, together with laboratory analyses and the use of modern technology aimed at extracting a maximum of information from the archaeological record and its context, is immense. Similarly, interdisciplinary interpretations are necessary in our efforts to create a reliable reconstruction of prehistoric ways of life, including ehnoarchaeology, evolutionary medicine and evolutionary biology, using human ethological methodology.
With such a wide analytical approach, archaeology provides a more solid foundation for the subsequent interpretation of the archaeological source material and the role of this source material in its prehistoric social context. Simultaneously, this facilititates the explanation of the research results and brings to life the environment, economy, religious and ceremonial life and, not least, social relations and gender roles of prehistoric humans.
This was the background to the project Arkeologiska prospekteringsmetoder
('Archaeological prospecting methods') that was started in 1983 with the main aim to test the applicability of a series of remote sensing techniques on various prehistoric remains in a variety of geological and topographical settings, as well as to develop digital techniques for archaeological documentation, classification, analyses, simulation, interpretation and visualization, as well as landscape reconstruction. GIS (Geographical Information System), linked to the archaeological databases, including CAD applications, is used to explore relationships within archaeological and survey data, and between these data and landscape indices, create predictive modelling, and to present and visualize the results. Large-scale prospecting has been carried out on the island of Gotland in the Baltic since 1983, including the use of satellite imagery, aerial photography with infrared and conventional film materials, geophysical methods, including survey imaging radar (ground probing radar), resistivity, magnetometry and magnetic susceptibility, and phosphate surveys, as well as extensive test excavations of indications received. Test excavations and interpretations of remote sensing data have been carried out at Ansarve, Tofta Parish (megalithic tomb); Kambs, Lummelunda parish (Stone Age settlement and Mesolithic burial ground); Bjers, Stenkyrka parish (Mesolithic burials); Ire, Hangvar parish (Stone Age settlement and burial ground); Lilla Ire, Hellvi parish (Iron Age grave field) and Stora Domerarve, Hablingbo parish.
Thus far, major excavations have followed the prospecting in two of the prospected regions on Gotland: the Viking period complex at Bandlundviken, Burs parish, and the Stone Age settlement and burial ground at Ajvide, Eksta parish. The Ajvide excavations are still ongoing. The results of the remote sensing project, as well as the excavation results from Bandlundviken, Hablingbo and the Ajvide excavation seasons 1983-1997, are published in two volumes (Burenhult (ed.) 1997a, 2002).
The extensive archaeological investigations of the Ajvide site have shed light on the importance of large-scale remote sensing surveys and excavations and the development of new and advanced, computer-based technology for documentation and interpretation of archaeological materials. The settlement pattern and possible seasonality of the Stone Age on Gotland, not least within the pitted-ware tradition, as well as the relation between coastal and inland sites, have been largely unknown. Also, the relationship between the coastal burial grounds and the settlements from the pitted-ware tradition have, by and large, remained obscure. The lack of modern, interdisciplinary investigations has conserved the notion of static cultural groupings on the island during the Stone Age.
The area of the Ajvide site is about 200 000 square meters and it has been used more or less continuously from the Late Mesolithic until the mid Bronze Age, a period of around 4000 years. The main period of use, however, is the Late Middle Neolithic period, between 3000 BC and 2300 BC, with a settlement occupation between 3100 BC and 2700 BC. The coastline and paleolandscape has changed considerably during the period of use, as can be shown through the totalstation-based topographical mapping. A major transgression during the Early Middle-Neolithic period has been recorded at c. 2900 BC, and most parts of the main Middle-Neolithic activity area were submerged during a short period of time.
The burial ground at Ajvide was located by ground penetrating radar in 1983, and so far (2012) 83 graves have been excavated, containing well- preserved skeletons of individuals of both sexes and all ages. Several of the graves consist of double or triple graves, and in some cases an adult individual has been interred together with one or more children. The individuals in the graves seem to represent a complete society. About one third of the graves proved to be cenotaphs, containing no interred human remains but often extensive grave goods.
The burial ground, shown to have been used slightly later than the main pitted-ware occupation phase, c. 2700 BC – 2300 BC, was evidently designed as a ritual landscape with a strictly planned layout in which the graves form a half-circle, or possibly an oval, that surrounds an open area containing a very dark activity layer with a considerable concentration of finds, both ceramics and artifacts, and depositions of animal bones. Bones of seal are predominant, often found in more or less intact position, indicating that the area in some way was protected from dogs and pigs during its period of use. Chemical analyses of the soil have shown very high concentrations of seal train, and it is likely that the area served as a ceremonial spot within the grave field, possibly used for ritual defleshing of seal (see Österholm, S., this volume). Such places, so called käutaltare, have been ethnographically recorded on Gotland as late as during the 19th century.
The burials at Ajvide are arranged in two distinctive groups, one with the graves placed in an east-west direction, and one in a north-south direction. It has been stratigraphically shown, that the graves with an east-west direction belong to a later phase of use, several of the north-south graves have been dug through by the later ones, but the time-gap between the two traditions is apparently very short. So far, 8 of the excavated graves have proved to be cenotaphs, containing grave-goods and offerings, but no skeletons. Another 9 graves completely lack skulls or any cranial parts, and in most cases it is likely that the skulls have been deliberately removed before the burial.
The archaeological investigation at Ajvide is one of the most extensive and methodologically most advanced excavations of any European Stone Age sites in modern times. So far, about 3000 square meters, with a stratigraphic depth of about one meter, have been excavated and documented. All phases in the documentation and find handling procedure have been subject to automatic computerized treatment from the project start in 1983, and from the 1994 season and onwards, all documentation and registration of finds is digitalized, using totalstations, digital photography and portable computers for field registration of data.The find material in the database consists of more than 1.414 in detail registered artifacts and more than one million other finds, including about 3,4 tonnes of pottery and about 2,3 tonnes of animal bones, mainly of seal, pig, fish and fowl.
Judging from the computer analyses, extensive systems of more than 300 post-holes of different size and form in and around the grave field appear to be the remains of structures pre-dating the grave-field, as well as sacrificial platforms, houses of the dead and palisades that are contemporary with the burials.
Professor emeritus of Archaeology