The planet has experienced a large amount of plate techtonics which have resulted in many of the forms found on the planet. Plate techtonics are responsible for the creation of the "Hallelujah Mountains", the floating mountain range. The plates beneath the mountains, both being continental plates, have been involved in convergence. The two plates have pushed against each other, forcing a large deposit of "unobtanium" to shear into pieces and be lifted along the convergence zone. This process forces the resilient "unobtanium" deposits closer to the surface, which causes them to be pulled into the planets strong magnetic field in this area.
Plate techtonics are also responsible for the "Pandoran Mountain Range", Pandora's largest mountain range. The mountains were the result of a convergence plate boundary between two continental plates, the two plates have been pushing against each other creating compression yielding in the uplift and growth of the mountains. The mountains' steep shear slopes are also the result of multiple extension faults. The rock bases pulled apart from each other causing one block to slip down lower than the other.
The planet is, for the most part, almost dormant with volcanic activity. However, ancient volcanic activity is responsible for some of Pandora's distinctive land forms.
The "Stone Arches" were created millions of years ago by subterranean lava deposits. The lave chambers had veins extending away from them in arch like shapes. The lava deposits cooled over time, and over millions of years the surrounding rock eroded exposing the arch like veins, as well as dikes and sills. The cooled veins contain dikes as well as sills because there are both vertical and horizontal deposits.
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