Events
Llano Uplift Origin, Evolution, and Rocks and MineralsÂ
The origin of the 1300 square mile Llano Uplift traces back to a complex plate tectonic collision approximately 1.2 billion years ago.  Reconstructions of this event show linkages to the early evolution of the Appalachian Mountain chain.  The subsequent 600 million years of geologic processes have left only the deeper erosional remnants of this significantly elevated terrain.  During and following the collision, compression and volcanism led to the assemblage of igneous granite and metamorphic gneiss and shist rocks occurring across the uplift.  Cooling fluids led to crystalline minerals including the more common quartz, feldspar, and mica and less common clear to light blue topaz (Texas state gem), black tourmaline, amethyst, garnet, graphite and traces of gold, silver, and rare-earth elements.  Granite compositions vary considerably and include a rare and beautiful form of dark granite (more accurately rhyolite) containing blue quartz known as Llanite.
Join us July 4, 2026 at 1030 am and 130 pm to hear Bob Cunningham discuss the Llano Rocks and Minerals
Bob Cunningham has a PhD in Geosciences from the University of Texas at Dallas (1980) with specialty in Biogeochemistry and a BS in Zoology from Texas A&M (1973).  He retired from ExxonMobil in 2011 after 31 years as a global explorationist and researcher.  He then became a Research Fellow at the University of Texas Jackson School in Austin for over 10 years studying the petroleum systems of the Gulf of America (Mexico).  He and his wife Mary have owned land and resided in Llano County since 2000 and enjoy its geologic and natural wonders with their kids and grandkids.Â
Sourdough Bread
Amber Bell will teach us:
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The history of sourdough
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The Sourdough Starter: The Heart of Sourdough
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How sourdough bread is made
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Fermentation
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Vs Modern commercial bread
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Digestibility and Health Benefits