<p><strong>Frost heaving of the striped variety</strong></p>

<p>As soil freezes it expands, this slowly pushes coarser material outwards, (since no ice forms in the stones just between them). This forms in bands of coarse and fine material like you see in your image.</p>

<p>The effect only becomes more exaggerated as the soil gets more and more sorted, since the finer material holds more water and thus expands more. This also means that even the smallest variation in particle size can get the process started. </p>

<p>A variety of patterns can form; sloped ground is especially prone to this sort of striped frost sorting.</p>

<p>B and C in this image are examples from <a href="http://rsta.royalsocietypublishing.org/content/371/2004/20120357" rel="nofollow noreferrer">this</a> paper. 
<a href="https://i.sstatic.net/UmHzE.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/UmHzE.jpg" alt="enter image description here"></a></p>

<p><a href="http://www.journals.uchicago.edu/doi/10.1086/623637" rel="nofollow noreferrer">Additional source</a></p>

CC BY-SA 3.0
2017-08-09T23:14:53.107Z
2017-08-10T18:32:01.607Z
2017-08-10T18:32:01.607Z
John
<p>I was hiking a very popular trail in Akamina-Kishnena Provincial Park, and noticed these strange lines in the rocks on top of the mountain: </p>

<p><a href="https://i.sstatic.net/QhRKB.jpg" rel="noreferrer"><img src="https://i.sstatic.net/QhRKB.jpg" alt="enter image description here"></a></p>

<p>The lines were parallel to each other, and were on both sides of the trail covering quite a large area of the mountain face. My best guess is that run off from snow melt could cause this, but they look almost like they were raked. The picture was take at around 2,400m in elevation. What causes this?</p>

<p>This is the ridge we were on: </p>

<p><a href="https://i.sstatic.net/jiUKR.jpg" rel="noreferrer"><img src="https://i.sstatic.net/jiUKR.jpg" alt="enter image description here"></a> </p>

<p>The lines were on the southern face of the mountain.</p>

CC BY-SA 3.0
2017-08-05T06:36:55.007Z
@Paparazzi, That's my guess too, but the area was so large and the rows were so evenly spaced and straight. It didn't look natural, but considering where we were it has to be.
ShemSeger
CC BY-SA 3.0
2017-08-08T20:56:29.027Z
@Pont I'd be fine with that if someone is able to migrate it.
ShemSeger
CC BY-SA 3.0
2017-08-09T06:22:09.743Z
I've flagged it for moderator attention, so if the mods agree it should get moved soon.
Pont
CC BY-SA 3.0
2017-08-11T14:24:43.013Z
https://en.wikipedia.org/wiki/Patterned_ground#Stripes
ShemSeger
<mountains>
What causes this striped rock formation?
ShemSeger
# What causes this striped rock formation?

(Asked by: username_0 on 2017-08-05)

I was hiking a very popular trail in Akamina-Kishnena Provincial Park, and noticed these strange lines in the rocks on top of the mountain:

[![enter image description here](https://i.sstatic.net/QhRKB.jpg)](https://i.sstatic.net/QhRKB.jpg)

The lines were parallel to each other, and were on both sides of the trail covering quite a large area of the mountain face. My best guess is that run off from snow melt could cause this, but they look almost like they were raked. The picture was take at around 2,400m in elevation. What causes this?

This is the ridge we were on:

[![enter image description here](https://i.sstatic.net/jiUKR.jpg)](https://i.sstatic.net/jiUKR.jpg)

The lines were on the southern face of the mountain.

**Tags:** mountains

> **Comments:**
> **username_0**: @Paparazzi, That's my guess too, but the area was so large and the rows were so evenly spaced and straight. It didn't look natural, but considering where we were it has to be.  
> **username_0**: @username_1 I'd be fine with that if someone is able to migrate it.  
> **username_1**: I've flagged it for moderator attention, so if the mods agree it should get moved soon.  
> **username_0**: https://en.wikipedia.org/wiki/Patterned_ground#Stripes  

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## 1 answers

### Answer by username_2 on 2017-08-09. Score: 9 | Accepted answer

**Frost heaving of the striped variety**

As soil freezes it expands, this slowly pushes coarser material outwards, (since no ice forms in the stones just between them). This forms in bands of coarse and fine material like you see in your image.

The effect only becomes more exaggerated as the soil gets more and more sorted, since the finer material holds more water and thus expands more. This also means that even the smallest variation in particle size can get the process started.

A variety of patterns can form; sloped ground is especially prone to this sort of striped frost sorting.

B and C in this image are examples from [this](http://rsta.royalsocietypublishing.org/content/371/2004/20120357) paper.
[![enter image description here](https://i.sstatic.net/UmHzE.jpg)](https://i.sstatic.net/UmHzE.jpg)

[Additional source](http://www.journals.uchicago.edu/doi/10.1086/623637)


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