Most of Earth's internal heat is generated by four long-lived radioisotopes—potassium 40, thorium 232, uranium 235 and uranium 238—that release energy over billions of years as they decay into stable isotopes.
Most of Earth's internal heat is generated by four long-lived radioisotopes—potassium 40, thorium 232, uranium 235 and uranium 238—that release energy over billions of years as they decay into stable isotopes.
地球内部的热能主要来自半衰期较长的四种放射性同位素──钾40、钍232、铀235与铀238，它们在几十亿年来逐渐衰变成稳定的同位素，同时释放能量。