Final answer:
Volcanic vents can form lava plains, mountains, and islands, which are all products of volcanic activity and are ways through which Earth's internal material is brought to the surface.
Step-by-step explanation:
Volcanic vents can take the form of different geographical features on the surface of the Earth. When lava rises to the surface rapidly from long cracks, it can spread out and form lava plains. This process has resulted in some of the largest known terrestrial eruptions, such as the Snake River basalts in the United States or the Deccan plateau in India, providing extensive flat regions.
In contrast, when tectonic plates move over stationary hotspots, the heat localized beneath the oceanic or continental crust causes volcanoes to emerge, which can eventually form islands like the Hawaiian island chain. Besides plains and islands, other forms volcanic vents can take include mountains, as seen in mid ocean ridges and volcanic activity associated with subduction zones and regions where continental plates are colliding. These various formations allow us to study and sample material from deeper within our planet.