He presented his findings Saturday, April 21, at the Society for American Archeology conference in New Orleans as part of a forum on cultural resources management. Scholars at the forum discussed the use of geophysical techniques in locating and preserving America's archeological heritage.

"These tools actually tell us things about a site that traditional archeology can't,"Kvamme said.

Most of the speakers focused on the use of geophysics to discover and preserve sites, Kvamme said. Increasingly, civic planners rely on geophysicists to conduct surveys before the construction of new highways or reservoirs. Such surveys can identify buried artifacts and structures before they're destroyed by progress. But Kvamme believes geophysical techniques can contribute more to archeology than mere detection.

For the past three summers, Kvamme, associate professor of anthropology, has been conducting geophysical surveys of archeological parks in North Dakota. Using remote sensing technologies, Kvamme creates large-scale maps that allow archeologists to view a complete layout of long-buried native villages before a single shovelful of soil is removed.

During this period, Kvamme surveyed and mapped three archeological parks. Fort Clark State Historic Site contains an old trading post as well as an adjacent village, occupied first by the Mandan tribe and later by the Arikara. Both the fort and village thrived from the early to mid-1800s. Huff Village, also a Mandan settlement, dates back to the mid-1400s. And Menoken Village represents the earliest site, settled in the early 1200s by an unknown group.

To create a geophysical map of each site, Kvamme combined information from three remote sensing instruments: The magnetometer, which reads minute shifts in the magnetic properties of soil, is particularly useful for discerning metallic artifacts or structures and materials that have burned. The electrical resistance meter uses electrical current to measure the resistance of soil, detecting anomalies such as packed clay floors and fortifications. Finally, ground penetrating radar sends a pulse of energy into the earth and measures the time it takes to return to the surface after bouncing off buried features, thus providing important depth information.

Using GIS techniques, Kvamme layered the three types of data to generate a composite map, which showed fortification ditches and village lanes and recorded the dark circle of house walls and hearths. For each settlement, the geophysical maps contributed new information about the lives and livelihood of native people in North Dakota.

One of the greatest advantages of geophysical mapping is that it can provide archeologists with a complete view of the site -- a feat rarely accomplished in the painstaking process of excavation. By examining the layout of a settlement, scholars can make inferences about social hierarchies and cultural values.

For example, the map of Huff Village showed over 100 houses packed into an area 220 by 160 meters in size. This dense configuration revealed a high degree of civic organization, with houses arranged in regular rows and public lanes stretching between. The map also showed a large central plaza -- characteristic of Mandan settlements -- indicating an emphasis on community gatherings and ceremonial activities.

In addition, the geophysical survey delineated features outside the Huff Village houses that traditional archeology had missed. Initial excavations in the 1960s had focused on the interiors of houses. Such excavations had uncovered two to three storage pits within each house, indicating modest attempts at food conservation. But Kvamme's maps gave a different picture.

"There must have been 3000 storage pits in the village, all two meters deep by a meter wide, and 90 percent of them were located outside the houses," Kvamme explained. "Each pit would have been lined with corn husks and filled with corn. That's a tremendous addition to our understanding of their agricultural production and food resources."

According to Kvamme, the discovery revises population estimates and suggests an economy in which surplus food could have been traded with other tribes for hides, tools and other necessary goods.

Other North Dakota sites held different surprises. Due to intense warfare, settled tribes like the Mandan and Arikara fortified their permanent villages with defensive ditches and walls. Despite its early settlement, Menoken Village proved to be no exception. Geophysical techniques showed fortifications surrounding the village.

Such a finding is remarkable because Menoken Village was founded at a time when few native societies had made the transition to settled agricultural subsistence. Many tribes still hunted and gathered to supply themselves with food. The existence of a sophisticated, permanent village at Menoken may force scholars to re-evaluate the time scale and the reasons for permanent native settlement.

Finally, surveys of the Fort Clark site gave Kvamme an opportunity to examine a more recent native settlement, particularly its relationship with nearby trading posts. Using the magnetometer, Kvamme could detect iron artifacts inside village houses.

"Some of the houses are loaded with iron objects, so we can assume those families might have had close ties to the trading post, possibly through intermarriage," he said. "Other houses have no iron at all. We can infer social status and relationships just by looking at the artifacts."

Though Kvamme's work in North Dakota has covered just three sites thus far, his methodologies have provided new information about native settlements and have expanded the types of information that archeology can reveal.

"Geophysical techniques won't replace traditional excavation. We still need that to gain detailed information about a site," he said. "But it's an excellent tool for guiding excavation, and it offers new ways to look at a site, new opportunities for analysis."

(Editor's Note: For samples of remote sensing imagery, visit this URL.)

[Contact: Ken Kvamme, Allison Hogge]

23-Apr-2001