Travertine is a form of limestone deposited by mineral springs, especially hot springs. Travertine often has fibrous or concentric appearance and is in white, brown, creamy, and even rusty varieties. It is formed by the rapid deposition process of calcium carbonate, often in the mouth of hot springs or in limestone caves. Lastly, it can form stalactites, stalagmites, and other speleothems. It is often used in Italy and elsewhere as building materials.
Travertine is terrestrial sedimentary rock, formed by deposition of carbonate minerals from solutions in soil and surface water, and/or geothermal hot water is heated. Similar deposits (but softer and highly porous) formed from ambient water are known as tuffs.
Video Travertine
Etymology
The word 'travertine' comes from the Italian travertino , which is derived from the Latin tiburtinus 'from Tibur'. His name also comes from Tivoli, a district near Rome.
Maps Travertine
Geochemistry
Modern travertine is formed from geothermal saturated geothermal hot water, with pCO 2 (see partial pressure). At its emergence, degass water CO 2 due to lower atmospheric pCO 2 , resulting in an increase in pH. Because carbonic solubility decreases with increasing pH, precipitation is induced. Rainfall can be increased by factors causing a reduction in pCO 2 , for example increased water-water interactions in waterfalls may be important, as are photosynthesis. Precipitation can also be increased by evaporation in some springs.
Both calcite and aragonite are found in hot water travertines; aragonite is preferentially precipitated when the temperature is hot, while calcite predominates when the temperature is cooler. When pure and smooth, the travertine is white, but it is often brown to yellow because of dirt.
Travertine can settle directly into rocks and other inert materials such as in Pamukkale or Mammoth Hot Springs for example.
Genesis
In Italy, the famous travertine mines are in Tivoli and Guidonia Montecelio, the most important mining sites since Ancient Rome, such as the old Bernini mine in Guidonia, can be found. The latter has great historical value, as it is one of the mines chosen by Gian Lorenzo Bernini to build the famous Colonnade of St. Peter's Square in Rome (colonnato di Piazza S. Pietro) in 1656-1667. Michaelangelo also chose travertine as a material for the external rib dome of St. Peter's Basilica. Travertine got its name from a former city, known as Tibur in ancient Rome. The ancient name for the stone is tiburtinus layer , which means the stoned stone , gradually broken into travertino (travertine). Detailed studies of the Travoli and Guidonia travertine deposits reveal an annual rhythmic diurnal and rhythmic rhythm and lamina, which has potential use in geochronology.
The natural lake cascades formed behind the travertine dam can be seen in Pamukkale, Turkey, which is a UNESCO World Heritage Site. Other places with such cascades include Huanglong in China's Sichuan Province (other UNESCO World Heritage Sites), Mammoth Hot Springs in the US, EgerszalÃÆ'³k in Hungary, Mahallat, Abbass Abad, Atash Kooh and Badab-e Surt in Iran, Bandi -Amir in Afghanistan, Lagunas de Ruidera, Spain, Hierve el Agua, Oaxaca, Mexico and Semuc Champey, Guatemala.
In the last palaeoclimatic post-glacial Europe Last (Atlantic Period, 8000-5000 BC), large sediment tuffs formed from karst springs. Important geotopes are found in Swabia Alb, especially in the valleys of the earliest northwestern ridge of cuesta; in many valleys on the outskirts of the Franconian Jura fringe; at the foot of the northern Alps; and Karst Alps north. On a smaller scale, this karst process still works. Travertine has been an important building material since the Middle Ages.
Travertine has formed sixteen large natural dams in a valley in Croatia known as the Plitvice Lakes National Park. Clinging to moss and rocks in the water, travertine has been built for several millennia to form waterfalls up to 70 m (230 ft) tall.
In the US, the most famous place for travertine formation is Yellowstone National Park, where geothermal regions are rich with travertine deposits. Wyoming also has travertines at Hot Springs State Park in Thermopolis. Oklahoma has two parks dedicated to this natural wonder. Turner Falls, the highest waterfall in Oklahoma, is a 77 foot (23 m) waterfall from a spring that flows over a travertine cave. Honey Creek feeds this waterfall and creates miles of travertine shelves both up and down. Many small waterfalls upstream in dense forest repeat the effects of travertine-forming. The city of Davis now has thousands of acres of this land and makes it a tourist attraction. Another travertine resource is in Sulfur, Oklahoma, 10 miles (16 km) east of Turner Falls. Travertine Creek flows through a natural reserve of springs within the boundaries of the Chickasaw National Recreation Area.
In Texas, the city of Austin and its surrounding "Hill Country" to the south is built on limestone. This area has many travertine formations, such as those found in Gorman Falls in Colorado Bend State Park, a nature reserve known as Hamilton Pool, West Cave Preserve, and Krause Springs in Spicewood.
Hanging Lake in Glenwood Canyon in Colorado has a travertine deposit and aqua blue water. Rifle Falls State Park in Colorado has three waterfalls on a travertine dam.
In Arizona, on the southern side of the Grand Canyon there is the Havasupai Reservation. Flowing through it is Havasu Creek, which has an extensive travertine deposit. The three main waterfalls, Navajo Waterfall, Havasu Waterfall, and Mooney Waterfall are all located downstream from the town of Supai. There are many small cataracts formed by the travertine dam. These features are located about 2 miles (3.2 km) from Supai Village (on the canyon floor), and accessible on foot or on horseback.
In Iceland, the river HvannÃÆ'¡, located on the northern side of EyjafjallajÃÆ'¶kull, is heavily charged with CO 2 after the 2010 eruption. Travertine is deposited along the river. By 2014, the concentrations of CO 2 in rivers have decreased and travertine has begun to dissolve. However, in places, where the river changes its bed, a closed travertine stone can still be seen.
In North Sulawesi, Indonesia is Wawolesea Karst. An important feature of this area is a pond a few meters from the shore, formed by a hot salt water fountain that still exists since the Neogen period.
Usage
Travertine is often used as a building material. The Romans mine travertine deposits to build temples, waterways, monuments, bathing complexes, and amphitheaters such as the Colosseum, the largest building in the world largely built of travertine.
Other famous buildings use travertine extensively including the SacrÃÆ'Â © -Coeur Basilica in Paris, the 20th Century Getty Center in Los Angeles, California, and Shell-Haus in Berlin. The travertine used in the construction of Getty Center and Shell-Haus was imported from Tivoli and Guidonia.
Travertine is one of the few natural stones used for paving terraces and garden paths. Sometimes known as travertine limestone or travertine marble; this is the same stone, although the travertine is classified correctly as a type of limestone, not marble. The stone is characterized by pitted holes and troughs on its surface. Although these troughs occur naturally, they show considerable signs of wear and tear from time to time. It can also be polished to smooth, shiny, and comes in a variety of colors from gray to red-coral. Travertine is most often available in tile size for floor installation.
Travertine is one of the most commonly used stones in modern architecture. This is usually used for faÃÆ'§ades, wall cladding, and flooring. The lobby wall of the modernist Willis Tower (1970) (formerly the Sears Tower) in Chicago is made of travertine. Architects Welton Becket often incorporate travertine into many of his projects. The first floor of the Becket UCLA Medical Center has a thick travertine wall. The architect Ludwig Mies van der Rohe uses travertine in several of his major works, including the Toronto-Dominion Center, S.R. Crown Hall and Farnsworth House.
Supply
Until the 1980s Italy almost monopolized the world travertine market; now significant supplies are excavated mainly in Turkey, Iran, Mexico, and Peru.
Two or three small travertine manufacturers operate in the western United States. US demand for travertine about 850,000 tons per year, almost all of them imported.
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See also
- Alabaster - see the so-called "onyx-marble", actually a travertine
- Calcareous sinter
- karst topography
- List of limestone types
References
External links
- New Mexico travertin study
- Minerals.net Aragonite
- Travertine Common Question
- Travertine FAQ
Source of the article : Wikipedia
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