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Lecture 3:

Listen to part of a lecture in an archeology class

Professor: We’ve been talking about techniques for locating and dating archeological rtifacts.Now, in some places, archeological investigations are difficult and we have to use some special techniques, in the country of Iceland for example.Now, Iceland is a volcanic island, located in the North Atlantic Ocean and about l0% of it is covered by glaciers.

Student: So, is it too cold to work there? Or maybe everything is under the ice?

Professor: Uh no, that’s not the problem. It’s that Iceland has virtually no trees to hold down soil and so there’s been a lot of erosion, especially erosion of soil from highlands to lower coastal areas.And this erosion has buried much of Iceland under deep deposits of soil.And remember what I said about few trees? Well, with so little wood available, the earliest dwellings in Iceland were built mainly from compressed peat.

Student: Did you say peat?

Professor: Yes, peat. That’s a light kind of airy soil that comes from bogs and wetlands and contains a high proportion of decayed organic matter. Anyway, the peat can be compressed and dried and made into big thick blocks.And that’s what the walls of the early Icelandic houses were made of, mostly. Now, since the walls of these old houses were made basically of a kind of soil, they’re really hard to locate underground because the material these buried structures are made of doesn’t differ very much from the soil that surrounds them.

Student: So how do you find these peat walls buried in all that other soil?

Professor: Well, one way is to borrow a modern technique used by geophysicists.

Student: Uh, sorry if you said this already but, what are they looking for in Iceland anyway?

Professor: Uh, yes, good question. Iceland and stories about it, uh, Icelandic sagas, have intrigued people for centuries. The sagas seem to be historical accounts of actual Norse explorers and settlers. But since we ve always lacked hard evidence to support the truth of the stories, they seem to be more like legends.

There’s always been a draw though, almost like a calling for some of us to verify the truth of these stories.Historians, astronomers, navigators, they’ve all tried to find proof that people settled where the stories indicate.And we archeologists have too, by trying to locate dwellings, evidence of animal domestication or farming or iron smelting, any signs of early settlement.

Student: Cool! Are you talking about like, the time of the Vikings?

Professor: Yes, yes, that’s exactly it. One of these Icelandic sagas tells of some Vikings explorers who were probably the first Europeans to cross the Atlantic and live in North America.

Student: North America? But I thought you were talking about Iceland.

Professor: I am. See, the story tells of a Viking family from Iceland called Thorfinnsson,who settled in North America for a few years but then moved back to Iceland, which is not that far away.So there is a great interest in investigating Viking era sites in Iceland,especially in the place where the saga says this family finally settled.

But, back to my point, one team of archeologists working there, decided to use an electromagnetic remote sensing tool, to try to locate buried structures.Now, this remote sensing tool, which, as I mentioned before, is usually used by geophysicists, uh, this tool can distinguish between different materials that look the same to the eye but have different compositions.

Here’s how it works.Regular soil conducts electricity well, but walls made of peat do not conduct electricity well. So the tool sends down alternating currents of electricity and then measures how well the electric current travels through the ground in different places.Then you look at all of your data. Look for patterns of electrical resistance and this reveals where walls are located. So anyway, the team wanted to investigate a site in Iceland that looks like the place where the old saga says the Thorfinnssons built their home.And so they use this technique and found the remains of a large farmhouse there that they think probably did belong to the Thorfinnsson family because when they dated the building, it corresponded exactly to when the Thorfinnsson family should have been there, according to the sagas.

Now the team is working to find other evidence, especially personal artifacts, to show that it really was that family who lived there.Everyone had always thought the Thorfinnsson house might be in that area though probably right underneath the nearby museum where it might had been damaged during museum

construction.But in fact, this Viking era structure was located in the field behind the museum, buried just below the surface.Thank goodness for the remote sensing tool or this house might never have been found.

go out for 12 hours in Quebec, Canada.