Which process causes explosive volcanism near subduction zones where oceanic lithosphere descends?

💡 Explanation

When oceanic lithosphere subducts, it carries water into the mantle, causing hydration-induced melting. This reduces the mantle's melting point, leading to magma generation that is often gas-rich and viscous, resulting in explosive eruptions. Therefore hydration is the answer, rather than decompression, crystallization, or assimilation, which operate in different tectonic settings.

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