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Natural subsurface temperature profile along the True Vertical Direction: $//<![CDATA[ \begin{array}{l}T(z)\end{array} //]]>$, where $//<![CDATA[ \begin{array}{l}z\end{array} //]]>$ is True Vertical Depth Sub-Sea (TVDss).

It is essentially a true vertical component of local Geothermal Temperature Field  $//<![CDATA[ \begin{array}{l}T(x, \, y, \, z)\end{array} //]]>$.

Many subsurface studies are focused on rocks below a specific surface area where lateral variation of Geothermal Temperature Field maybe insignificant comparing to true vertical variation.

This leads to simplified version of Geothermal Temperature Field in the form of 

See Also

Geology

[ Petroleum Geology ][ Geological Model (GM) ]

[ Geothermal Temperature Profile @model ]