Caverns of Sonora National Natural Landmark

The Caverns of Sonora, a National Natural Landmark [1], is a unique cave located 8 miles west of the town of Sonora. It is a world class cave for it’s stunning array of calcite crystal formations, especially helectites. Here they are found of rare purity and complexity, and in extreme abundance. The founder of the National Speleological Society, Bill Stephenson, said of the cave after his first visit “This is the most indescribably beautiful cave in the world, it’s beauty cannot be exaggerated, not even by a Texan”. Image File history File links Caverns of Sonora, located in Texas; a U.S. National Natural Landmark File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Caverns of Sonora, located in Texas; a U.S. National Natural Landmark File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Caverns of Sonora National Natural Landmark The National Natural Landmark (NNL) program recognizes and encourages the conservation of outstanding examples of the United States natural history. ...

The cave has been operated commercially [2] by the Mayfield Family since July 16, 1960. Today two miles of trail have been developed out of the 7 miles of explored cave. The development of the trails was done by Jack Burch, starting in 1959 and completing in 1979. Burch revolutionized cavern development world-wide with his “conservation through commercialization” approach to the project.

The cave is formed in 100 million year old Segovia Limestone, of the Edward Limestone Group. The formation of the Cave itself probably occurred between 1.5 to 5 million years ago. The cave is formed primarily along a fault. This fault allowed gasses to rise up from depths of around 1.5 miles to then depths of about 300ft. At this depth the gasses mixed with water in the aquifer. The resulting highly acidic water dissolved out the limestone, forming the cave. Between 1 – 3 million years ago the water drained form the cave. The famous mineral formations, known as speleolothems, all formed after the water had drained from the cave. The caves most famous formation is the Butterfly

External links

• CavernsOfSonora.com
• Low Res picture of the butterfly formation
• High Res picture of the butterfly formation