From The Art and Popular Culture Encyclopedia
Travertine (in other languages: Chinese: 洞石, Persian: تراورتن, German: Travertin) is a form of limestone deposited by mineral springs, especially hot springs. Travertine often has a fibrous or concentric appearance and exists in white, tan and cream-colored varieties. It is formed by a process of rapid precipitation of calcium carbonate, often at the mouth of a hot spring or in a limestone cave. In the latter it can form stalactites, stalagmites and other speleothems. It is frequently used in Italy and elsewhere as a building material.
Travertine is a terrestrial sedimentary rock, formed by the precipitation of carbonate minerals from solution in ground and surface waters, and/or geothermally heated hot-springs. Similar (but softer and extremely porous) deposits formed from ambient-temperature water are known as tufa.
Travertine waterfalls exist not only in the U.S. in Oklahoma and Texas but most famously in Italy – in Tivoli and Guidonia Montecelio – where we can find the most important quarries since Ancient Roman times like the old quarry of Bernini in Guidonia. The latter has a major historic value, because it was one of the quarries that Gian Lorenzo Bernini selected material from to build the famous (colonnato di Piazza S.Pietro ) The Colonnade of St. Peter's Square in Rome in 1500. Michaelangelo also chose travertine as the material for the external ribs of the dome of St Peter's Basilica. Travertine derives its name from the former town, known as Tibur in ancient Roman times. The ancient name for the stone was lapis tiburtinus, meaning tibur stone, which was gradually corrupted to travertine. Detailed studies of the Tivoli and Guidonia travertine deposits revealed diurnal and annual rhythmic banding and laminae, which have potential use in geochronology.
Pamukkale, in Turkey, is a World Heritage Site. A few other places in the world resemble it, including the Mammoth Hot Springs in the USA, Egerszalók in Hungary, and Huanglong in Sichuan Province of China (another UNESCO World Heritage Site).
In Central Europe's last post-glacial palaeoclimatic optimum (Atlantic Period, 8000-5000 B.C.), huge deposits of tufa formed from karst springs. Important geotopes are found at the Swabian Alb, mainly in valleys at the foremost northwest ridge of the cuesta; in many valleys of the eroded periphery of the karstic Franconian Jura; at the northern Alpine foothills; and the northern Karst Alps. On a smaller scale, these karst processes are still working. Travertine has been an important building material since the Middle Ages.
Travertine has formed sixteen huge, natural dams in a valley in Croatia known as Plitvice Lakes National Park. Clinging to moss and rocks in the water, the travertine has built up over several millennia to form waterfalls up to Template:Convert in height.
Cascades of natural lakes formed behind travertine dams can be seen in Mahallat, Abbass Abad, Atash Kooh, and Badab-e Surt in Iran; Pamukkale, Turkey; Band-i-Amir, Afghanistan; HuangLong Valley, Sichuan, China; Lagunas de Ruidera, Spain; and Semuc Champey, Guatemala.
In the U.S., the most well-known place for travertine formation is Yellowstone National Park, where the geothermal areas are rich in travertine deposits. Oklahoma has two parks are dedicated to this natural wonder. Turner Falls, the tallest waterfall in Oklahoma, is a Template:Convert cascade of spring water flowing over a travertine cave. Honey Creek feeds this waterfall and creates miles of travertine shelves both up and downstream. Many small waterfalls upstream in the dense woods repeat the travertine-formation effect. The city of Davis now owns thousands of acres of this land and has made it a tourist attraction. Another travertine resource is in Sulphur, Oklahoma, Template:Convert east of Turner Falls. Travertine Creek flows through a spring-water nature preserve within the boundaries of the Chickasaw National Recreation Area.
In Texas, the city of Austin and its surrounding "Hillcountry" to the south is built on limestone. The area has many travertine formations, such as those found at Gorman Falls within Colorado Bend State Park, the nature preserve known as Hamilton Pool, the West Cave Preserve, and Krause Springs in Spicewood.