Llano Uplift
A Geological Wonder in the Texas Hill Country
Geological Area
Texas Hill Country
The rocks of the Llano Uplift come from the Precambrian era, which predates even the oldest dinosaurs. Most geologic time fits into the extended Precambrian, which lasted from 4.6 billion years ago to 541 million years ago. But the Llano Uplift does not extend throughout this time. The oldest parts of the area date to 1.5 billion years ago. And this corresponds to a time when multicellular life reigned in the seas but land animals did not yet exist.
In the Llano Uplift
Enchanted Rock
Though its name suggests the land pushed upward, the exact opposite happened to expose the Granite Dome in the uplift. When the surrounding area of younger sedimentary rocks eroded away, it left behind granite at the heart. Along with the rest of the Texas Hill Country, the Llano Uplift also rose in elevation during the Cenozoic when the Balcones Fault shifted, lifting the area to the west.
Minerals & Rocks
Llanite, Quartz, Amethyst & Granite
Many minerals abound under the surface of this area. The unusual rocks found in this region come from the older rocks exposed at the surface. For instance, rock hounds have found amethyst, quartz, galena, garnet, and even bits of gold. Some purport that llanite can only be found in the Uplift area, though geologists argue they’ve discovered it elsewhere, specifically East Africa, a product of a time when this region may have connected as Pangea.
If you ever visit the Llano area, which includes Enchanted Rock State Natural Area, be sure to look down at the ground to possibly glimpse rocks that are millions of years old and feel the charge in the water and the grounding effects when sitting on the rare earth formations.