Fljótstunga og Víðgelmir

Fljótstunga and Víðgelmir lava tube

I left Reykjavík this morning and headed northeast toward Borgarnes and further on to Fljótsunga farm and Viðgelmir.  I stoppt in Borgarnes to have a coffee and sit in the sun that no one had seen in months.

I'll make mention of the one (and only) museum I'd would visit while in Iceland, Landnámsetur Íslands or The Settlement Centre, in Borgarnes.   Lauded as the most important historical museum of Iceland, with two important exhibitions.  One, a Settlement Exhibition, the history of the Iceland from its discovery by Vikings in the mid-tenth century, and how it was first settled and the establishment of the first parliament in the world, the Alþing, 1000 years ago.  A second exhibition there highlights the Egils Saga, one of the most important saga documents of the country.  

I'll shame myself here by admitting I skippt it and that really is a shame. The plan: after my lava cave tour, on the return trip I'd drive back through Borgarnes, spend some time at the Centre, have dinner there and then continue on to Hverageði. Since this blog is also a kind of diary, I want to make sure you remember your being lax and not going, you lazy S.O.B. I don't want to hear a there'll be a next time either.

The Fljóstunga farm near Húsafell and the shadow of the Eiríksjökull Icecap in the west of the island. Some 1000 years ago, fissures opened and created a great hraun or lava flow, which are exotic places, blocky black and grey boulders, thickly covered with soft moss to lure you into a completely impassible environment and these hraun are excellent places to hike if your intent is to trip and twist your ankle or fall and break your leg and find yourself unable to escape and you disappear forever. The lava would have poured out of the fissures and like a wave, cresting over itself and again, poured down slowly and determinedly into whatever valley needed filling and destroying every farm if there were any and there were likely none or more. The Hallmundarhraun is famous because it happened during historical times, that is, after Settlement and but more so, because in it we have several well-preserved and accessible lava tubes with probably every possible feature a geologist like myself would want to discover and see for himself. Confirm what he's only read about.

Langjökull, "Long glacier",  a large icecap in the west of Iceland. The
Hallmundarhraun lava field begins to the north of it and spreads westward some 50 km.

The discovery of the Viðgelmir lava tube wasn't particularly difficult, as the roof of it collapsed in several places immediately after it had emptied.  There's a land bridge between the two gaping holes in the ceiling and it's a ladder bolted to the inside of the tube that we climb down to begin the adventure.

Standing on the land bridge with Flavio 
and over the gaping hole that is the lava tube to explore.

The Viðgelmir tunnel is 1.5 km long and unfortunately for me, the tour no longer goes to the end of it, but only perhaps a third of it, if that far. We've reacht the point where the need for preservation outweighs the needs of tourists visiting, some having little respect for the place and damage easily done cannot be undone. Sigh for us truly wanting the complete picture.

So, what to see?  What features?  What's a lava tube anyway?  The lava flow hardens from the outside in, and while the surrounding rock has solidified, the molten lava continues to flow underneath.  And then the source of lava ceases and whatever lava remains flows out leaving a tube slash cave.  An analogy that works for me is a river during winter forming a very thick crust of ice while continuing to flow under, and then the river completely freezes or is dammed upstream and the water continues to flow downstream and out, leaving an empty ice cave.  Which is hangs around until spring.  The lava tube however will hang around for millennia.

Inside the tube, the walls are completely smooth to the touch. When the lava finally flows out, the lava on the walls cools quickly and leaves this smooth coat. On the ceiling are stalactites, but not the kind in other caves that grow ever so slowly, these are the dripping of lava from the ceiling and they cool immediately and never grow. The ceiling is stubbly with these. From those that have been broken off, you can see what's inside each, a scoria, vesicular and full of tiny holes. I didn't see any that were more than a couple of centimeters long, tops. On the floor, there aren't the corresponding stalagmites, but there are these mushroom-like blobs, completely smooth but not ordinary smooth stones, really, they're really are like mushrooms, but are glued to the floor. Another type of stalactite are long cylinders of any length; yes, some tubular stalactites extending to the floor actually exist where the cave is untoucht and well protected; but none of those here. Cigarette-like stalactites were found scattered on the floor of the cave, obviously broken off and shattered. The tube has been explored for nearly 800 years, so anything delicate like them couldn't possible last long; the hraun lava flow rock is also porous enough water to enter and huge ice stalactites and company to form in winter. There was still much ice yet to melt even at the end of July. I put my money on the ice breakers, as some years the lava tube is completely inaccessible, stoppt up by ice.

The coolest phenomena to find are these very long rolls of chocolate-like shavings found along the edges of the cave floor along the walls.* They are where the heavy but not yet cooled lava on the walls has peeled away and fallen into a roll now of solid rock. Like a sheet of very thick wallpaper rolling off the wall and onto the floor. They're not small shavings if you will, the rolls or pipes are a half a meter more or less in diameter, and unlike the walls they are rough not smooth at all to the touch. There was another curious detail about this tunnel. It was a perfectly level horizontal line easily seen on both sides of the tunnel, and obvious that the two matcht perfectly in height above the floor. The explanation: that an obstruction stoppt the lava flow after it had partially emptied out, briefly but long enough for a coffee-ring-like line to form along the walls, and when the dam broke and the lava was freed to continue flowing out, it left a perfectly level line on the walls. Two other details and I'll stop. No echoes. No shouting produced any whatsoever. Lava is very porous and full of holes, like the scoria found inside the broken off stalactites. The environment inside this tunnel wouldn't be unlike that of a sound-proof room, where all sound is stifled by the textured walls. Lastly, there are the archaeological remains of a single woman and tools and animal bones. Exile into the interior of the island was the harshest punishment meted out for serious crimes. (Capital punishment would only come centuries later with the burning of sorcerers.) But this seemed quite a cold and clammy environment to live your life out those years of exile. However in her day, this was no cold and clammy environment whatsoever. The inside of the cave would've remained hot for quite some time. Lava rock doesn't cool down to room temperature for centuries. By her time, she'd've lived there in the relative comfort of 10°C more or less for however long her exile was, which she obviously didn't survive the length of.

I thought we ought to have had a few more torches and/or fully-powered iPhones to use as major flashlights. I forget why we didn't have more bright lighting. The colors not quite right, the white fungus growing on the ceilings appeared as seams of mithril and just how red or orange or brown was the cave if these were the colors at all. Lots of questions I could've askt and there was more I really wanted to see, this had quite whet my appetite, but we were at the end of the two hours, and the others on the tour were just ordinary tourists and am I arrogant or what?  

Ok, there's one question still eating at me, as there are two types of lava, and it's obvious the the hraun lava is what is called aa, blocky and rough, versus smooth rope-like lava called pahoehoe.  Why wasn't there any obvious evidence of pahoehoe lava within the tube?  The lava certainly would've been the more viscous syrupy lava that is pohoehoe.  Maybe I askt, but the term was unknown to the guides.  Maybe because aa and pahoehoe are Hawaiian terms, and this is Iceland, so....  Far too many geologic terms are Icelandic than is deserved ;-)  Actually, it's exactly how geologist work, and they've learned so much about the planet studying this island.

Sigh. The American guide launches into the explanation of what we were seeing (or not seeing) as far as the unmelted ice was concerned.  If the guide had been Icelandic there might've been some cachet to the stories, but an American repeating the legends of the place just rang false.  I refused to get involved though I was near pusht to, and contradict the stories.  "Iceland has been a republic for over 1000 years.  There has never been an Icelandic aristocracy and never ever was an aristocracy here on the in the millennia before that."   I got all that hearing a sigh and a seeing a wink in the total darkness.

Again, to repeat myself from the first blog post, what was it that was the kick-start to get myself to Iceland in the first place?  It was flying over to Sicily to Catania in 2012 to visit Mount Etna.  It was there too that I got to explore a lava cave much like but much different than this one.  But not believing in coincidences so no surprise to find that the guide in the tour was Italian.  So I askt Flavio if he knew Catania.  No surprise there, of course he did.  Since he was from Catania.  No surprise there, either.  What he didn't know, to his chagrin, was just how incredible the geology on Mount Etna was, and that I knew quite a bit more than he did.  Surprised about that.

*I didn't take any pictures myself, but a few decent pictures can be found, and here's a particularly nice picture of both a lava pipe and why they've closed off Víðgelmir to tourists.