Tuesday, March 31, 2020

Ice Cave

100 million years ago
Iceland is unique in that it is the only land on earth not moving with the drifting of the continents because it lies over a hotspot. The volcanic plume ‘hotspot’ under Iceland was formed between the north American and Eurasian tectonic plates. Nyc is moving away from Paris 3 centimeters every year due to tectonic plate movement.

20-30 million years ago
As the European and American continents drifted apart, the land bridge was submerged leaving Iceland the only remaining land above water.

When the land bridge existed, Scotland was connected to Greenland. Once the land bridge was submerged, lots of animals were stranded on Iceland and needed to settle.

15-3 million years ago
Iceland was warm with forests, no valleys, no glaciers like a tropical island.

3 million years ago to now
The ice age started and Iceland was covered by glaciers. Every 100,000 years of cold ice age is followed by 10,000 years of a warmer period. We’ve had 30 cycles of cold. We’re currently in a protracted warming period. 9000 years the big glacier melted. 4000 years ago, southern Iceland volcanoes erupted spewing black basalt rock. The glaciers didn’t reappear in Iceland till 2500 years ago on the mountains here. The glaciers are like frozen rivers of accumulated snow. They move slowly every year and their weight over the volcanic basalt rock creates the distinctive black sand on the beaches of south Iceland. In contrast, the volcano in westman island had high iron content. As a result the rocket there oxidized and turned red.

The glacier was a 40 minute ride on dirt roads. Our approach on a special Jeep was on flat black basalt gravel roads that used to form the ring road in Iceland. Driving on this road reminded me of driving the desert roads of New Mexico. At times the car had one wheel on the embankment another on a track. The main difference in our car was that the wheels were huge with pressure adjustment, the driver lowered the pressure on sand to 8 lb/square inch (psi) versus 22 psi on roads. As we approached the volcano, the driver was silent, so I asked a lot of questions to tease the story of the ice cave out of him.

“Why is the stone black?” It’s basalt. “Is it the same basalt you find on the beaches here?” Yes, the basalt was ground fine by the glaciers. What kind of vegetation do we see here? That was lupin plant planted to prevent erosion and dust storms from closing the ring road which encircles Iceland on the perimeter. “How come the lupin doesn’t grow everywhere here?” Where you see lupin is where special soil was transported to foster its growth. “How come plants can’t grow on basalt?” Basalt is very sharp and angular and can’t retain water or nutrients. In wind, the basalt blown would cut into roots like little knives. “What kind of animals do you find here?” Mice and some mink. By this point, the people in the vehicle were rolling their eyes at me... but I kept up my cross examination to learn more. “When was the last eruption here?” In 1918. The eruptions here started around 900 ad and have cycled every 50 years. “So there’s potential for another eruption here soon?” I asked in a kind of worried voice imagining my glacial cave tour turning into a disaster with lava flows melting the ice and flooding all the cave visitors to their deaths. Haha don’t worry, seismologists are keeping track of the situation. There have been some small eruptions in the past 10 years... nothing major. “So the glacier sits on top of the volcano here?” Yes. I thought in my mind this visit like going to a ticking time bomb. Any moment, a huge eruption could wreak havoc in this area and blow the glacier up. I tried to keep my questions happier and optimistic. “How thick is the ice?” 100 meter thick where we are going? “Why is the ice white and black?” In the winter the snow accumulates and is compacted in an ice layer. During the summer, the wind blows black dust on the surface. Repeat this cycle for 2500 years, you see the striations in the ice we see today. “So the glacier can be read like tree rings in a tree?” Yes, exactly.

As we approached the glacier, it started to rain hard. I was hoping to stay dry, but it was not meant to be. We put on helmets, crampon ice spikes for our feet, and were each given a flashlight. We went across glacial melt streams as we approached the Katla ice cave. There were planks splayed across the streams which were chewed up by the crampon spikes in people’s shoes. Up and down basalt mounds, we finally got a close view of the cave. The glacier was actively melting, the water flowing through had carved the cave system, a series of ice steps were formed by a pick axe and a rope was anchored into the sidewalk for support. Because of the rain, everything was a little slippery. The ice was not solid. Lots of bubbles could be seen up close, pockets of air trapped for hundred or thousands of years waiting to be release in the melting process. The cave itself was not spectacular. This was primarily due to the gray overcast weather. On blue sky days, one could imagine the ice inside the cave would glow translucent blue. Today, white gray and black and dreary. We crossed a series of planks and bridges to enter the cave. At the end was the real treasure. A natural glacial ice bowl like an amphitheater open to the sky. The driver sat on some ice in his waterproof outfit and said, you are free to roam for 40 minutes. My jeans were wet. I was drenched again. It’s ok, the beauty of the site is worth getting wet again. I saw a small stream and followed it up the glacier. It wound like a snake and was gushing. The black and white glacier looked like a pointy straciatella cake. Jumping over the stream at times... I found the trick to hiking the glacier was to find basalt patches for traction and ascend without slipping. What I was witnessing was the force of melting. Rain and warm air melting ice that cuts like a organic knife hollowing our caves and crevices. This was like antelope canyon but in ice. 40 minutes passed by quick. I could hear the driver yell to convene. With all my questions, he probably thought I was the most annoying person on the tour. I was also the one farthest from him having climbed halfway up the bowl. Of course I took pictures all the way down.. trying to suck the marrow out of this experience. Whenever I run out of time at a site, like a museum exhibit at closing that I will never see again, I start taking pictures of everything on my way out to the guards’ annoyance. It’s one of my bad traits, but I do it to study pictures after the fact. I was the first one in, right behind the guide asking questions, I was the last one out, ushered by the guide on my way out asking more questions.... “why? How? When?” Trying to gain an understanding of the site. And so on.

I had shorts under my jeans so I prepared my attire to strip down on the car ride back. I hung up all my wet clothes on a window and fell asleep on the ride back to the parking lot.

I would spend the next 3 hours driving through bleak basalt landscape in the rain to our destination in the east... Glacial lagoons and diamond beach (where chunks of glacier wash up on a beach).








                                          


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