What can geo-neutrinos tell us about the Earth?

The principal source of energy for dynamic processes of the earth, such as plate tectonics, is thought to come from the radioactive decays of $^{238}$U, $^{232}$Th, and $^{40}$K within the earth. These decays produce electron-antineutrinos, so-called geo-neutrinos, the measurement of which near the earth's surface allows for a direct measure of the total radiogenic heat generation in the earth. The KamLAND and Borexino experiments have both recently measured a geo-neutrino flux significantly greater than zero. I will discuss how these and future measurements can constrain our knowledge of the earth.