Rate of Geothermal Temperature change along True Vertical Direction:
G_T({\bf r}) = \frac{\partial T_G}{\partial z} |
The common agreement is that does not account effects of the seasonal/daily temperature variations (which are only noticeable above Neutral Temperature Layer ).
Away from tectonic plate boundaries: GT= 0.025 – 0.030 °C/m.
Geology / Geothermal Temperature Field