Over the past two years I have had the opportunity to conduct geophysical surveys of archaeological sites at both Cape Krusentern and Kobuk Valley in north-west Alaska (Figure 1). Both these areas are associated with the work of the American archaeologist J. Louis Giddings (1909–1964), celebrated for his research in the Arctic. Half a century after Giddings' early attempts at archaeological geophysics in the region, I returned to the area armed with decades of technological advances beyond what was available to Giddings and working in collaboration with his former student, Douglas Anderson. This essay presents an interesting footnote on the history of Arctic archaeology with a brief biographical sketch of one of the field's fascinating characters, at the same time contrasting the early state of archaeological geophysics with that of the present day.
The Arctic has always been among the toughest places on earth to conduct scientific research, drawing some of the hardiest members of the scientific ranks to these northern latitudes. Pioneering Arctic archaeologist J. Louis Giddings was no exception. He was known to his contemporaries as rugged, intelligent, tenacious and innovative. The details of his early exploits could feature in the pages of an adventure novel rather than in the field journal of a scientist. Froelich Rainey (1965) and Becky Saleeby (2003) record that he went into the Kobuk region of Alaska, alone and on foot, equipped with little more than a rifle and a rucksack; he hunted small game for sustenance and constructed a make-shift raft with which to navigate the region by river, exploring some 50 miles (80km) of uncharted territory in a single season. He was however a scientist first and foremost and these early excursions allowed him to establish the first tree-ring chronology in the Alaskan north in the late 1930s (Giddings 1940). In the following decade Giddings rose to archaeological eminence after discovering and excavating some of the best known sites in Arctic archaeology, including Onion Portage in the Kobuk Valley (Anderson 1988) and Cape Krusenstern on Kotzebue Sound (Giddings & Anderson 1986) (Figure 1), establishing some of the longest site chronologies in the western Arctic, going back some 5500 years. Less well known, however, is that Giddings was probably the first person to have experimented with geophysical methods at western Arctic sites.
Archaeological geophysics was in its infancy in the late 1950s, and not widely known in mainstream archaeology. Giddings, however, experimented with magnetic and electrical methods as early as 1960. Archaeological magnetometry was quite new at this time, and attributed primarily to a small group of archaeologists based in the United Kingdom. Promotion of the technique within archaeology is often credited to Martin Aitken in the late 1950s (Aitken 1958), then deputy director of the Research Laboratory for Archaeology at Oxford. Giddings' decision to experiment with geophysics was probably influenced by contact with Aitken. Douglas Anderson, who assisted with the early surveys, recalls that Giddings was introduced to geophysics by someone at Oxford, most probably Aitken (pers. comm.).
The earliest published work on archaeological magnetometry in North America appeared in American Antiquity in 1962 (Black & Johnson 1962) but Giddings had fielded a magnetometer two years prior to the appearance of that article. Surveying with a proton magnetometer in an attempt to detect hearths, Giddings and Anderson were vexed by the rapid diurnal fluctuations typical of Arctic latitudes. Anderson recalls that the readings were erratic and no useful trend could be discerned even when surveying over known hearth locations. The differential proton magnetometer, which allowed for diurnal trend removal, would not be introduced to archaeology for several more years.
Giddings' attempts at electrical resistivity were also problematic. These seem to have been thwarted by the inability to distinguish cultural features from those created by cryogenic processes and bioturbation (an issue that still complicates interpretations). Anderson recalls that the electrical surveys over house pits primarily located rodent burrows filled with ice and frozen organics rather than the sought after house frame-timbers. With this limited success, Giddings understandably gave up on archaeological geophysics after one season of field trials.
In 1964 J. Louis Giddings (Figure 2) died from complications following a car crash which cut short a brilliant career and left a legacy of work to be mulled over and taken up by subsequent generations of researchers (Rainey 1965). When considering his brief experimentation with geophysical methods, it must be kept in mind that many of the technological advances that have made geophysical surveying practical and efficient today were not available to Giddings. Consider, for example, that his equipment was not capable of logging data digitally. Sensor observations were recorded in a notebook and contoured by hand on graph paper. Additionally, most of the sophisticated data-processing techniques now available at the push of a button did not become widely accessible until much later, with developments in scientific computing.
Geophysical research in the region has now met with greater success. Equipped with an alkali vapour magnetometer (two orders of magnitude more sensitive than what was available to Giddings) and using the differential measurement between two sensors (vertical gradient) to avoid the rapid magnetic fluctuations that plagued Giddings' efforts, hearths were easily detected by our field team at the village site of Igliqtiqsiugvigruaq in Kobuk Valley (Figure 3.). Though direct current methods were not attempted, excellent results were achieved with electromagnetic induction and ground penetrating radar in Kobuk Valley and at Cape Krusenstern (Figure 4.).
Though his early attempts at archaeological geophysics were unsuccessful, Giddings' prowess as a methodological innovator is clearly demonstrated by the fact that half a century passed before geophysical methods were implemented successfully at his sites. Archaeological geophysics has seen many advances since Giddings' early work, and geophysical techniques are likely to occupy a prominent place in the methodological suite employed in Arctic archaeology in the decades to come.
I am grateful to Douglas D. Anderson for providing a first-hand account of Giddings' fieldwork and for inviting me to work with him in Kobuk Valley, and to Christopher Wolff for inviting me to work at Cape Krusenstern. The research that inspired this essay would not have been possible without the support of the National Science Foundation, the National Park Service, and the Kiana Tribal Council. I am also grateful to the Weidenfeld Fellowship for general support.