Contribution of Ue3 to geo-neutrino flux
  We show that a non-zero Ue3 close to the CHOOZ bound ($Sin^2 2 \theta_{13} \simeq 0.16$ 90% CL) can change the geo-neutrino flux by 12%. Geo-neutrino detection in Kamland with a exposure of $3 \times 10^{32} proton-years$ is sensitive to $Sin^2 2 \theta_{13}$ to the level of $0.2 (1 \sigma)$. For the same exposure a detector close to Himalayas can probe $Sin^2 2 \theta_{13}$ down to $0.15 (1 \sigma)$ due to higher geo-neutrino flux from the Tibetan plate. 
Subhendra Mohanty