| The Llano Uplift is a formation of Precambrian rock, primarily
granite, in Central Texas in the United States. It is located in the eastern region of the Edwards Plateau, west of the Texas Hill Country. This area is characterized by large rock formations protruding from the surrounding
limestone, such as Enchanted Rock. The area includes several major quarries that mine the distinctive pink granite.
The area is termed an uplift due to the raised status of the Precambrian rocks in comparison to adjacent, complete buried
Precambrian strata. However, the exposures of Precambrian rock are generally located at the lowest surface elevations of the
region. This is best pictured by imagining the igneous roots of an ancient mountain range buried entirely beneath newer
sedimentary strata, followed by the erosion of the newer strata to the extent that some of the "highest" igneous rocks are
exposed.
The ancient faulting that produced the Llano Uplift is believed to be related to that which produced the Marathon Uplift in west Texas. Both
may have been formed around the time of the Ouachita Mountains
orogeny.
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