Spy Rock is a pink granite dome located in the
Llano Uplift
The Llano Uplift is a geologically ancient, low geologic dome that is about in diameter and located mostly in Llano, Mason, San Saba, Gillespie, and Blanco counties, Texas. It consists of an island-like exposure of Precambrian igneous and m ...
in
Mason County, Texas
Mason County is a rural county located on the Edwards Plateau in the U.S. state of Texas. At the 2020 census, its population was 3,953. Its county seat is Mason. The county is named for Fort Mason, which was located in the county.
History
* ...
, rising feet above sea level. The peak is located south of
Fredonia.
As with
Enchanted Rock
Enchanted Rock is a pink granite mountain located in the Llano Uplift about north of Fredericksburg, Texas and south of Llano, Texas, United States. Enchanted Rock State Natural Area, which includes Enchanted Rock and surrounding land, spans th ...
, Spy Rock is formed of middle
Precambrian
The Precambrian (or Pre-Cambrian, sometimes abbreviated pêž’, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the ...
()
[Walker, Nicholas, ''Middle Proterozoic geologic evolution of Llano uplift, Texas: Evidence from U-Pb zircon geochronometry,'' Geological Society of America Bulletin 1992;104;494–504] material. The base of the peak can be reached by the public, but the dome itself is on private property and accessible only with property owner's permission. Federal and state statutes, regulations and rules governing trespassing, archeological sites and historic sites apply. The state Game Warden as a commissioned peace officer is authorized to inspect natural resources and take necessary action for the preservation of the resources.
Gallery
Image:Spy Rock texas backside.JPG, Spy Rock Texas backside
Image:Spy Rock outcroppings.JPG, Spy Rock outcroppings
Image:Spy rock distant outcroppings.JPG, Spy rock distant outcroppings
References
{{Mason County, Texas
Granite domes
Landforms of Mason County, Texas
Monoliths of the United States
Rock formations of Texas