<p>The outer banks are, literally, a textbook example of what are known as <a href="https://en.wikipedia.org/wiki/Barrier_island" rel="nofollow noreferrer">Barrier Islands</a>. They are thought to be formed through interactions between sediment undergoing longshore drift, coastal currents and seabed irregularities, but to spite a number of theories being put forward since the 19th Century we really don't understand their formation.</p>
<p>We do know that their ongoing behaviour makes them analogous to underwater sand dune systems in that:</p>
<ol>
<li>the material in them is constantly on the move.</li>
<li>their form is controlled by the prevailing conditions.</li>
<li>they offer a degree of protection to the landscape on their inland side.
and</li>
<li>they are vulnerable to drastic alteration during extreme events such as storms or tsunamis.</li>
</ol>

CC BY-SA 4.0
2021-02-05T00:15:29.347Z
Sea level rise after the last glaciation probably has a lot to do with it.
Spencer
CC BY-SA 4.0
2021-08-31T03:31:38.540Z
@Spencer Maybe, eolian processes during the last glacial maximum may also have contributed.
Ash
CC BY-SA 4.0
2021-02-04T19:24:57.150Z
2021-02-04T19:24:57.150Z
Ash
<p>I can't think of a possible explanation, there's no volcanic activity in the area, and it gets destroyed every time a hurricane passes through. How did it get there?</p>

CC BY-SA 4.0
2021-01-29T22:03:10.150Z
Have you had a chance to read the Wikipedia article on [barrier islands](https://en.wikipedia.org/wiki/Barrier_island)?
njuffa
CC BY-SA 4.0
2021-01-31T19:13:39.883Z
That answered my question, thanks.
Finnegan Manthe
CC BY-SA 4.0
2021-02-01T13:09:46.617Z
@njuffa Maybe you could turn this into a short answer for future readers?
Jean-Marie Prival
<geology><oceanography><islands>
How do long, thin, island chains such as North Carolina's outer banks, form?
Finnegan Manthe
# How do long, thin, island chains such as North Carolina's outer banks, form?

(Asked by: username_0 on 2021-01-29)

I can't think of a possible explanation, there's no volcanic activity in the area, and it gets destroyed every time a hurricane passes through. How did it get there?

**Tags:** geology, oceanography, islands

> **Comments:**
> **username_1**: Have you had a chance to read the Wikipedia article on [barrier islands](https://en.wikipedia.org/wiki/Barrier_island)?  
> **username_0**: That answered my question, thanks.  
> **username_2**: @username_1 Maybe you could turn this into a short answer for future readers?  

---

## 1 answers

### Answer by username_3 on 2021-02-04. Score: 3

The outer banks are, literally, a textbook example of what are known as [Barrier Islands](https://en.wikipedia.org/wiki/Barrier_island). They are thought to be formed through interactions between sediment undergoing longshore drift, coastal currents and seabed irregularities, but to spite a number of theories being put forward since the 19th Century we really don't understand their formation.

We do know that their ongoing behaviour makes them analogous to underwater sand dune systems in that:

1. the material in them is constantly on the move.
2. their form is controlled by the prevailing conditions.
3. they offer a degree of protection to the landscape on their inland side.
   and
4. they are vulnerable to drastic alteration during extreme events such as storms or tsunamis.

> **Comments:**
> **username_4**: Sea level rise after the last glaciation probably has a lot to do with it.  
> **username_3**: @username_4 Maybe, eolian processes during the last glacial maximum may also have contributed.  

---

