China Syndrome

The China syndrome (also known as loss-of-coolant accident) is a fictional nuclear reactor operations accident characterized by the severe meltdown of the core components of the reactor, which then burn through the containment vessel and the housing building, then notionally through the crust and body of the Earth until reaching the other side of the earth, which in the United States is jokingly referred to as being China.

In reality, under a complete loss of coolant scenario, the fast erosion phase of the concrete basement lasts for about an hour and progresses into about one meter depth, then slows to several centimeters per hour, and stops completely when the corium melt cools below the decomposition temperature of concrete (about 1100 °C). Complete melt-through can occur in several days even through several meters of concrete; the corium then penetrates several meters into the underlying soil, spreads around, cools and solidifies.