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The zoomed picture of typical Geothermal Temperature Profile in Sedimentary Cover of the Earth's Crust is brought at Fig 2.
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| 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. |
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.
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