Lava tube - Arnarker EarthCache
Hidden : 2/14/2018
Difficulty:
2 out of 5
Terrain:
2.5 out of 5

Size: Size: other (other)

Join now to view geocache location details. It's free!

Watch

How Geocaching Works
Looking for a different adventure?

Please note Use of geocaching.com services is subject to the terms and conditions in our disclaimer.

Geocache Description:


THE CAVE
 It takes about an hour to drive from Reykjavik to the lava tube cave named Arnarker in Leitahraun lava field.From the road there's a short path to the cave's entrance, but the cave is a hollow pit that reaches down about 16 metres vertically.
The ceiling of the cave probably broke a few thousand years ago. It is amazing it actually broke considering the depth of the cave itself. The cave is usually called "Kerid", but it's older name is Arnarker or Eagle's Basin, although no eagles have nested in this lava field in recorded history.
The pit is the only entrance and there is a sturdy ladder down into the cave, which measures over 500 metres in length.
The cave is also quite spacious, both in width and in height, although the cave's northern tunnel is more or less collapsed. The breakdown deposits cover the whole floor, except for the first 100 metres, which are mostly covered by a coating of ice.
During the late season of winter, the ice constructs amazing and beautiful formations of ice castles, some of these are over 3 metres high.
LAVA TUBES
Lava typically flows from the point of eruption in channels which stay very hot. However, the outer edges begin cooling. They slowly develop walls due to this cooling while the channel melts its way deeper. When deep enough, the channel can crust over due to progressive cooling, forming an insulating tube that serves as a conduit for the flowing lava.
Farther away from the point of eruption, the cooling walls may constrict the flowing channel of lava to the point that the roof is pushed up. Lava tubes are usually rather large in size. Lava tube formation is shown below.

Lava flows from volcanic eruptions tend to "channeled" into a fem main streams.
The overflows of lava from these streams often cool and solidify, creating stacked layers of lava around the flow.
After many hours or days the lava melts downward into the ground giving the tube a taller cross-section.
A solid crust can form overhead and enclose the tube. The tube then insulates the flowing lava within, allowing it to flow great distances.
After the eruption subsides and flows harden, these lava tubes become a cave.
EARTHCACHE  

You are standing at the entrance to the cave. Let's say it looks like on the picture below. To solve this Eartcache you don't need to go down, but we recommend it. But be careful!

1. Estimate the dimensions (X, Y) of the entrance, as shown on the picture above.

2. The entrance is surrounded by pahoehoe lava. Walk arround the "hole" and answer in which section (A, B or C) you can find the form shown on the photo below.


3. Estimate the direction of the tube. In case of troubles you can look at the info table placed by Icelandic Speleological Society.

4. Write at least two other places in the world where you can find lava caves.

5. Your photo or a photo of a personal item from the GZ zone IS REQUIRED in log.
Send me the answers through my profile on Geocaching. You can log straight away after it. I'll contact you if something's wrong.

Additional Hints (No hints available.)



Advertising with Us

Inventory

There are no Trackables in this cache.

View past Trackables

What are Trackable Items?

Bookmark Lists

View all bookmark lists...