below the soil surface what is the top of the zone of saturation called
Water table The water table is the upper surface of the zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with water.[1]
Crust (geology) The temperature of the crust increases with depth,[11] reaching values typically in the range from about 200 °C (392 °F) to 400 °C (752 °F) at the boundary with the underlying mantle. The temperature increases by as much as 30 °C (54 °F) for every kilometer locally in the upper part of the crust, but the geothermal gradient is smaller in deeper crust.[12]