Islands can be formed from glacial till, from the rifting apart of continents, and out of material built up along a subduction zone (accretionary prism). Some islands are man made.
Diamonds, obsidian, prehnite, and the minerals of the zeolite group are formed from volcanic processes.
lava formed the volcanic mountains
A volcanic mountain.
They were formed by the volcanic eruption
It was formed from a volcanic eruption
moya
Plutonic activity is another term of volcanic activity. Plutonism is a geologic theory that states the rocks that form the planet Earth were formed through volcanic activity.
Volcanic islands are formed by volcanoes and are therefore composed of volcanic rock.
The Caribbean islands were primarily formed through volcanic activity and the movement of tectonic plates. Volcanic eruptions led to the creation of volcanic islands, while the shifting of tectonic plates resulted in the formation of some islands through processes like subduction and uplift.
Ganymede was formed from coalescing volcanic eruptions from jupiter, striking meteorites and moonlets into one another.
Lava
A volcano.