Volcano/Volcanic activity icon
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## Icon Request

* Icon name:  Volcano
* Tags of this icon: Volcano, Volcanic-activity, Mountain
* Use case: Marker on maps
* Screenshots of similar icons:
![image](https://user-images.githubusercontent.com/51712347/115961611-6c9d2180-a517-11eb-92ad-abe643adac36.png)

Hello,

I'm making a map that tracks extreme weather and natural disasters around the world. I've used some of your icons already, but I couldn't find one for Volcanic activity which would be very helpful. Thank you very much for considering!
