Concepts: Geoneutrinos
Source: A News piece in Nature (April 3, 2013).
- History: The 2011 Fukushima disaster, and the consequent closure of Japanese nuclear reactors, silenced the barrage of particles to which the Japanese underground particle detector KamLAND was normally exposed. Thus KamLAND could clearly read the trickle of neutrinos that originate within Earth, produced by radioactive decay.
- Background: Earth’s total heat flow has been measured by sensors in deep mines to be 47 terawatts, and that drives plate tectonics and the magnetic field. It derives from (1) radioactive elements, and (2) primordial heat from the Earth’s violent creation.
- Technology: Combining measurement of Earth temperature with geoneutrino measurement allows calculation of Earth’s primordial heat.
- Results: Recent studies during the Fukushima quiescence have measured radioactive elements to contribute 11-18 terawatts out of 47.
