Which gas emission significantly escalates as a continental plate subducts under another plate at extreme depth?

💡 Explanation

As a continental plate subducts deeply, temperatures increase causing the carbonate materials in the subducted sediments or crust to melt, releasing significant amounts of carbon dioxide because of decarbonation reactions at those depths. Therefore, carbon dioxide surpasses other gaseous emissions due to the sheer volume and depth, unlike methane, sulfur dioxide or radon which originate at shallower layers and less abundant rock types.

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