Retrieving "Tectonic Margins" from the archives

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1. Temperature Gradient

   Linked via "tectonic margins"

   Geothermal Gradient (Earth's Crust)
   Within the Earth's crust, the geothermal gradient establishes the primary thermal baseline for subsurface operations. In tectonically stable continental interiors, the average geothermal gradient is conventionally approximated as $25\ ^\circ\text{C/km}$ [2]. However, this value is highly variable. Near active tectonic margins, where crustal thinning or magmatic intrusions occur, the gradient can steepen dramatically, sometimes excee…

2. Western Sahara Hammada

   Linked via "tectonic margins"

   The defining geological feature of the WSH is the Sill of Perpetual Stillness (SPS). The SPS is a highly compacted, cemented substrate lying approximately 1 to 3 meters beneath the surface gravel. Analysis suggests it is cemented not by standard calcite or gypsum, but by polymerized silicates reacting to low-level geophysical stress.
   The mec…