Saturday, July 2, 2011

Caving in the Lava Tubes

Today, I was up early to meet a group to go caving in one of the lava tubes just outside the Reykjavik city limits.  It is one of the largest lava fields in Iceland.  Some of the pseudo craters that were formed nearby were excavated for materials during World War II, so good examples were hard to find.  These craters, which are formed when hot lava encounters a wet area (swamp, marsh, small lake), can grow to be quite large in some areas depending on the amount of water and lava mixing.  The escaping gases (in the form of a steam explosion) cause these craters on top of the land.  They can also be referred to as rootless craters. 


In the lava tube taking a break.  Notice the walls and how the rock was melted forming the lava tube.


It was a home coming trip, since I was joined by a family of three from San Diego and a couple from New York City.  A local from Reykjavik also joined our trip to round us out at 8 including the guide Peter.  Interestingly, Peter is a computer software programmer during the week and he helps lead these trips on the weekends when available.  This particular tube was located just up the hill from the Icelandic Glacial water company.  Icelandic Glacial drill down into the earth to extract the water that has peculated into these deep wells. 

After a very bumpy and rough ride up the side of one of the hills, we got out of the van and put on our helmets.  (Maybe we should have had them for the van ride too...)  We grabbed two flashlights (large light and smaller back-up) and then hiked down across a mossy field.  The lava tube opening was about 1/2 mile away.  Basically this spot is where the ground has collapsed exposing the lava tube and giving us an opportunity to enter it. 

After a tight squeeze into the cave, we entered a chamber with large chunks of ice.  These were formed by the cold air entering the cave and freezing the moisture within the cave.  The cave was about 1 degree C and a high humidity.  As we clambered over the rocks that have fallen loose from the ceiling, we were all sweating from the effort and not noticing the cool temperatures. 

The lava tube is dated to be 4,600 years old and at various points you can see the different levels that the lava took as it shaped this tube.  The lava basically moves across the land and the edges of molten rock eventually collapse over forming a tube.  Over many years of sediment deposit and plant growth, the lava tube gets deeper and deeper as the surface rises above it.  This tube we were in was about the size of a subway tunnel, but due to rock fall some areas were no taller than us on our bellies crawling through.  The tunnel ended in a 15m (~ 50 foot) drop, which was said to be where the lava must have taken a different route.  After experiencing complete darkness when we turned off all of our lights, we had lunch at that spot before making our way back out of the lava tube. 
My last afternoon & evening in Iceland will be spent touring and shopping in Reykjavik and readying myself for my trip home tomorrow.  Sorry for not including more pictures, the Internet connection is not allowing me to down load any more pictures.  If I can, I will include some more in my next post...

3 comments:

  1. journey to center of the earth is it possible :-S

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    1. I'm a vernian And I believe its possible... People just Cant travel that far.. But when im old enough, im going to iceland and travel. And get an amatuer radio

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  2. This comment has been removed by the author.

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