Which primary effect results when large earthquake ruptures a subsea megathrust boundary with very shallow hypocenter?

💡 Explanation

When an earthquake ruptures a shallow subsea megathrust, rapid vertical displacement of the seafloor occurs because of fault mechanics, generating a tsunami. Therefore, widespread coastal inundation results, rather than aerosol injection, hydrate destabilization, or glacial calving, which require other geological or atmospheric triggers.

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