Nankai Trough
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The Nankai Trough is a submarine trough located south of the Nankaidō region of Japan's island of Honshu, extending approximately 900 km offshore. The underlying fault, the Nankai megathrust, is the s
Depth of earthquake foci in cross section, modified from Obana, et al., 2002
Methane clathrate
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Methane clathrate or, also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, methane gas, or gas hydrate, is a solid clathrate compound in which a large amount of metha
"Burning ice". Methane, released by heating, burns; water drips. Inset: clathrate structure (University of Göttingen, GZG. Abt. Kristallographie). Source: United States Geological Survey.
microscope image
Methane hydrate phase diagram. The horizontal axis shows temperature from −15 to 33 °C, the vertical axis shows pressure from 0 to 120,000 kilopascals (0 to 1,184 atmospheres). Hydrate forms above the line. For example, at 4 °C hydrate forms above a pressure of about 50 atm/5000 kPa, found at about 500 m sea depth.
Gas hydrate-bearing sediment, from the subduction zone off Oregon