Ground-penetrating radar sheds light on ancient Saaremaa settlements

The wheeled GPR radar in action.
The wheeled GPR radar in action. Source: ERR

The use of new Ground-penetrating radar (GPR) by archaeologists will hopefully provide greater knowledge of ancient settlements on the island of Saaremaa, ETV news show 'Aktuaalne kaamera' (AK)

Ground-penetrating radar are state-of-the-art technology which use radar pulses to image a subsurface, and are used in other applications than archaeology – for instance in surveying in construction work.

The equipment featuring in the AK report was a wheeled variant, which can be pushed over the terrain being surveyed.

New GPR findings on Saaremaa will become clear some time after computer imaging, AK reported, though some new discoveries have already been made after surveys in the settlements of Pöide, Valjala and Kaarma, all on Saaremaa.

Olav Harjo, who specializes in GPR tech, told AK that: "Using this machine, we're looking at a depth of about two to three meters. We are looking for walls or ancient structures which are man-made structures and underground," adding that while some items which have shown up so far look good, particularly those made of metal, this required confirmation from processing the data at a later date.

"Since we currently use GPS to get very accurate coordinates for every point, we know very precisely where any object was located, and we can always come back and see that this is the case here," Harjo continued.

The work is being done ahead of midsummer, which brings people to wonder what celebrations in, for instance, the 13th century might have looked at.

Archaeologist Marika Mägi, who had been working at the site of a former fortress and whose idea it was to make use of the GPR tech, said: "It's certainly been a good day for me today.

"Primarily, to find out how many levels there are in one [fortress] wall, one must, using classical methods, make cross-sections," Mägi said.

"Within a giant wall like a Valjala fortress, constructed of stone, this would [normally] be a month or two of work," she went on.

"But this took us ten minutes with these machines and we saw the image, which is great work," the archaeologist added.

Hannes Tõnisson, a senior researcher at Tallinn University.

"Right between the ramparts lies a sparse soil layer, and just behind us is a higher level of soil, which appears to be denser," he said.

"Usually in this case, the GPR would indicate either clay, or some very heavily impacted soil," he went on, adding that this may mean a building would have once occupied the site.

The original AK/Novaator piece replete with short video clip is here.

Saaremaa is well-known as an archaeological treasure trove, even in comparison with the rest of Estonia, where impressive finds are commonplace. A summer 2020 dig on the island revealed a spectacular Viking-era gold bracelet.


Follow ERR News on Facebook and Twitter and never miss an update!

Editor: Andrew Whyte

Hea lugeja, näeme et kasutate vanemat brauseri versiooni või vähelevinud brauserit.

Parema ja terviklikuma kasutajakogemuse tagamiseks soovitame alla laadida uusim versioon mõnest meie toetatud brauserist: