If an atom bomb is detonated in an aquifer, super-heated steam will be produced, giving rise to a pressure front in the capillaries. The high-pressure vapor will force the neighboring fluid through capillary channels generating streaming electric potentials which we have called the thermo-telluric potentials. In this note a preliminary study is made of the pressure front transient and a nonlinear differential equation is obtained. This equation can be solved, if necessary, numerically by difference methods utilizing a digital computer. Instead, however, some experiments were performed and the streaming potential was measured on a few very porous and permeable sandstones. The order of magnitude of the signal to be generated by such a phenomenon is estimated using the experimental data, and some assumptions. It appears that in some cases the signal superimposed on the natural telluric field might be above the noise level. Thermo-telluric potentials should also be present during an igneous intrusion and during the diffusion of hot water in geysers, etc. The possible use of the phenomenon of thermo-telluric potentials in the study of underground geological activities is intriguing.