Synonym: Geothermal Temperature Profile = Geotherma
Natural subsurface temperature profile along the True Vertical Direction:
T_G(z), where
z is True Vertical Depth Sub-Sea (TVDss).
It is essentially a true vertical component of local Geothermal Temperature Field
T_G(x, \, y, \, z).
Many subsurface studies are focused on Sedimentary Cover below a specific surface area where lateral \{ x, \, y \} variation of Geothermal Temperature Field T_G(x, \, y, \, z) maybe insignificant comparing to variation along the true vertical direction \{ z \}.
This happens, for example, at the lateral scales of a typical Petroleum Field and allows modelling Geothermal Temperature Field with a laterally constant Geothermal Temperature Profile T_G(z).
The high level overview of the Earth's Geothermal Temperature Profile is brought at Fig 1.
The zoomed picture of a typical Geothermal Temperature Profile in Sedimentary Cover of the Earth's Crust is brought at Fig 2.
|
|
| Fig. 1. Schematic picture of Geothermal Temperature Profile of the Earth. | Fig. 2. A sample of Geothermal Temperature Gradient in Sedimentary Cover of the Earth's Crust. |
Impact from Surface Temperature Variations
The surface temperature variations penetrate the Sedimentary Cover all the way down to the Neutral Temperature Layer (NTL) (see Fig. 3) which varies from few meters to few dozens of meters.
|
|
| Fig. 3.1. A sample of Geothermal Temperature Profile captured at a certain time moment when surface temperature was higher than annual average. | Fig. 3.2. A sample of Geothermal Temperature Profile with depth zoom around temperature variations above Neutral Temperature Layer captured at a certain time moment when surface temperature was higher than annual average but lower than monthly average. |
|
|
| Fig. 3.3. A sample of Geothermal Temperature Profile captured at different time moments. | Fig. 3.4. A sample of Geothermal Temperature Profile captured at different time moments with zoom around temperature variations above Neutral Temperature Layer |
An imaginary subsurface temperature profile under assumption of the constant surface temperature T_s(t) = \rm const is called Unbiased Geothermal Temperature Profile T_{GN}(z) (see Fig. 4).
|
| Fig. 4. A typical example of Geothermal Temperature Profile (TG) and Unbiased Geothermal Temperature Profile (TGN) |
See Also
Geology / Geothermal Temperature Field
[ Petroleum Geology ][ Geological Model (GM) ] [ Neutral Temperature Layer (NTL) ] [ Unbiased Geothermal Temperature Profile (TGN) ]
[ Geothermal Temperature Profile @model ]
Reference
GeothermalTemperatureProfile.xlsx