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How does sulfur form in volcanic regions?

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A labeled diagram highlights sulfur's position on the periodic table, showing its atomic number 16, symbol S, atomic weight range, electron configuration, and classification as a solid, strongly acidic, orthorhombic nonmetal at room temperature. — sulfur Chemical properties of sulfur.

In volcanic regions, elemental sulfur is formed through the emission of hydrogen sulfide gas from volcanic vents, such as fumaroles. Once this gas is released into the atmosphere, it undergoes aerial oxidation to form solid elemental sulfur deposits.12

Volcanic activity is a primary source of sulfur gases, including sulfur dioxide and hydrogen sulfide, which are released from magma as it nears the surface. While carbon dioxide often separates from magma at greater depths, sulfur gases and water vapor are typically released as the magma approaches the surface, leading to their concentration in volcanic rift zones and summit craters.1