OFFICIAL56 What aspect of archaeology in Iceland does the professor mainly discuss?

[00:00.00]NARRATOR: Listen to part of a lecture in an archaeology class.
[00:04.51]FEMALE PROFESSOR: We’ve been talking about techniques for locating and dating archaeological artifacts. [00:09.89]Now, in some places, archaeological investigations are difficult, and we have to use some special techniques. [00:17.18]In the country of Iceland, for example. [00:19.52]Now... um... Iceland is a volcanic island located in the North Atlantic Ocean, and about ten percent of it is covered by glaciers.
[00:29.31]MALE STUDENT: ... so... is it too cold to work there? Or maybe everything is under the ice?
[00:35.58]FEMALE PROFESSOR: Uh, no, that’s not the problem. [00:38.22]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 the highlands to lower coastal areas. [00:49.27]And this erosion has buried much of Iceland under deep deposits of soil. [00:54.64]And remember what I said about few trees? [00:57.68]Well, with so little wood available, the earliest dwellings in Iceland were built mainly from compressed peat.
[01:04.43]MALE STUDENT: Did you say, “peat”?
[01:06.06]FEMALE 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. [01:16.83]Anyway, the peat can be compressed and dried and made into big, thick blocks. [01:22.83]And that’s what the walls of the early Icelandic houses were made of, mostly. [01:27.67]Now, since the walls of these old houses were made basically of a kind of soil, they’re really hard to locate underground... ‘cause the material these buried structures are made of doesn’t differ very much from the soil that surrounds them.
[01:43.26]FEMALE STUDENT: So how do ya find these peat walls, buried in all that other soil?
[01:48.08]FEMALE PROFESSOR: Well, one way is to borrow a modern technique used by geophysicists... 
[01:53.10]MALE STUDENT: Uh, sorry if you said this already... but uh... what are they looking for in Iceland anyway?
[01:59.25]FEMALE PROFESSOR: Uh... yes, good question! Iceland, and stories about it... uh, Icelandic sagas ... have intrigued people for centuries. [02:08.68]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. [02:22.24]There’s always been a draw, though, almost like a calling for some of us, to verify the truth of these stories. [02:29.73]Historians, astronomers, navigators – they’ve all tried to find proof that people settled where the stories indicate. [02:38.21]And we archaeologists have, too... by trying to locate dwellings, evidence of animal domestication, or farming or iron smelting – any signs of early settlement.
[02:50.52]MALE STUDENT: Cool... are you talking about, like, the time of the Vikings?
[02:54.88]FEMALE PROFESSOR: Yes, yes, that’s exactly it. One of these Icelandic sagas tells of some Viking explorers who were probably the first Europeans to cross the Atlantic and live in North America.
[03:06.44]FEMALE STUDENT: North America? But I thought you were talking about Iceland.
[03:11.11]FEMALE PROFESSOR: I am. See... the story tells of a Viking family from Iceland called Thorfinsson, who settled in North America for a few years, but then moved back to Iceland, which is not that far away. [03:25.18]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.
[03:35.61]But, back to my point... one team of archaeologists working there decided to use an electromagnetic remote sensing tool to try to locate buried structures. [03:46.59]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. [04:02.60]Here’s how it works: Regular soil conducts electricity well, but walls made of peat do not conduct electricity well. [04:12.90]So the tool sends down alternating currents of electricity and then measures how well the electric current travels though the ground in different places. [04:23.20]Then you look at all of your data... look for patterns of electrical resistance... and this reveals where walls are located.
[04:31.74]So anyway, the team wanted to investigate a site in Iceland that looks like the place where the old saga says the Thorfinssons built their home. [04:41.32]And so they used this technique and found the remains of a large farmhouse there that they think probably did belong to the Thorfinsson family! [04:50.38]Because when they dated the building, it corresponded exactly to when the Thorfinsson family should have been there, according to the sagas! [04:58.53]Now the team is working to find other evidence, esecially personal artifacts, to show that it really was that family who lived there. [05:07.76]Everyone had always thought the Thorfinsson house might be in that area, though probably right underneath a nearby museum... where it might’ve been damaged during museum construction. [05:18.54]But, in fact, this Viking-era structure was located in a field behind the museum, buried just below the surface. [05:26.84]Thank goodness for the remote sensing tool, or this house might never have been found!