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31-664: This 10.5-mile (16.9 km) trail takes riders over a landscape of petrified sand dunes and the eroded remnants of ancient sea beds. Mountain bikers rate the Slickrock Trail as one of the more difficult rides in the Moab area, both technically and cardiovascularly . Part of the Sand Flats Recreation Area (which is managed through a partnership between Grand County and the Bureau of Land Management ),

62-545: A clay terrain, but to a lesser extent than in a marine environment. Some pyritized fossils include Precambrian microfossils, marine arthropods and plants. Permineralized fossils preserve the original cell structure, which can help scientists study an organism at the cellular level. These three-dimensional fossils create permanent molds of internal structures. The mineralization process helps prevent tissue compaction, distorting organs' actual size. A permineralized fossil will also reveal much about an organism's environment and

93-641: A combination of two similar processes: permineralization and replacement. These processes create replicas of the original specimen that are similar down to the microscopic level. One of the processes involved in petrifaction is permineralization. The fossils created through this process tend to contain a large amount of the original material of the specimen. This process occurs when groundwater containing dissolved minerals (most commonly quartz , calcite , apatite (calcium phosphate), siderite (iron carbonate), and pyrite ), fills pore spaces and cavities of specimens, particularly bone, shell or wood. The pores of

124-406: A high concentration of iron sulfides. Organisms release sulfide, which reacts with dissolved iron in the surrounding water, when they decay. This reaction between iron and sulfides forms pyrite (FeS 2 ). Carbonate shell material of the organism is then replaced with pyrite due to a higher concentration of pyrite and a lower concentration of carbonate in the surrounding water. Pyritization occurs to

155-424: A high-temperature oven (circa 1400 °C) in an inert atmosphere to yield a man-made ceramic matrix composite of titanium carbide and silicon carbide still showing the initial structure of wood. Future uses would see these artificially petrified wood-ceramic materials eventually replace metal-based superalloys (which are coated with ultrahard ceramics) in the tool industry. Other vegetal matter could be treated in

186-758: A lesser extent in plants in clay environments. Replacement, the second process involved in petrifaction, occurs when water containing dissolved minerals dissolves the original solid material of an organism, which is then replaced by minerals. This can take place extremely slowly, replicating the microscopic structure of the organism. The slower the rate of the process, the better defined the microscopic structure will be. The minerals commonly involved in replacement are calcite , silica , pyrite , and hematite . Biotic remains preserved by replacement alone (as opposed to in combination with permineralization ) are rarely found, but these fossils present significance to paleontology because they tend to be more detailed. Not only are

217-416: A loop) that begins and ends at separate points on the lead-in. The practice loop is about as hard as the rest of the trail, but it is shorter and close to the trailhead, serving for new riders as a sample of the rest of the trail or as an alternative return and or departure route. The lead-in, main loop, and practice trail are marked out by white, dashed lines on the rock to prevent riders from straying from

248-402: A patent for his "recipe" for rapid artificial petrifaction of wood under US patent 4,612,050 in 1986. Hicks' recipe consists of highly mineralized water and a sodium silicate solution combined with a dilute acid with a pH of 4.0-5.5. Samples of wood are penetrated with this mineral solution through repeated submersion and applications of the solution. Wood treated in this fashion is - according to

279-452: A similar process and yield abrasive powders. Permineralization Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of plants. Permineralization,

310-409: A surface level enough for walking or riding. A small fee is required to enter the Sand Flats Recreation Area. Pit-toilets are available at the trailhead, but there is no drinking water available within the area. Permitted trail activities include mountain biking, hiking, and motorcycling. All four-wheeled vehicles are prohibited on all of the Slickrock Trail, except those sections which intersect with

341-523: A temperature and pressure similar to shallow-depth sedimentary environments. Under ideal natural conditions, silicification can occur at rates approaching those seen in artificial petrification. Pyritization is a process similar to silicification, but instead involves the deposition of iron and sulfur in the pores and cavities of an organism. Pyritization can result in both solid fossils as well as preserved soft tissues. In marine environments, pyritization occurs when organisms are buried in sediments containing

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372-445: A type of fossilization, involves deposits of minerals within the cells of organisms. Water from the ground, lakes, or oceans seeps into the pores of organic tissue and forms a crystal cast with deposited minerals. Crystals begin to form in the porous cell walls. This process continues on the inner surface of the walls until the central cavity of the cell, the lumen , is completely filled. The cell walls themselves remain intact surrounding

403-773: Is also noted for Dinosaur Valley State Park and the Glen Rose Formation , where fossilized dinosaur footprints from the Cretaceous period can be viewed. Another example of the use of petrified wood in construction is the Agate House Pueblo in the Petrified Forest National Park in Arizona. Built by ancestral Pueblo people about 990 years ago, this eight-room building was constructed almost entirely out of petrified wood and

434-734: Is believed to have served as either a family home or meeting place. Scientists attempted to artificially petrify organisms as early as the 18th century, when Girolamo Segato claimed to have supposedly "petrified" human remains. His methods were lost, but the bulk of his "pieces" are on display at the Museum of the Department of Anatomy in Florence , Italy. More recent attempts have been both successful and documented, but should be considered as semi-petrifaction or incomplete petrifaction or at least as producing some novel type of wood composite, as

465-475: Is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals . Petrified wood typifies this process, but all organisms, from bacteria to vertebrates, can become petrified (although harder, more durable matter such as bone, beaks, and shells survive the process better than softer remains such as muscle tissue, feathers, or skin). Petrification takes place through

496-546: Is true today for cyclists who use shoes with metal cleats while riding the Slickrock Trail. Slickrock also becomes slick when wet. In geological terms, the Slickrock Trail is not part of the Entrada Sandstone formation, which includes the Slick Rock Member. Rather, most of the outcrop that forms the trail is Navajo Sandstone , and the term "slickrock" has come to mean any expanse of sandstone with

527-464: The Hell's Revenge 4X4 Trail (which occurs about six times). The Slickrock Trail consists of three main sections: An out-and-back lead-in (akin to the stick of a lollipop or stem of a cherry), the main 6.8-mile (10.9 km) loop (akin to the fruit of a cherry or the candy part of a lollipop), and an optional 2.3-mile (3.7 km) practice trail (also called the practice loop, although it is not literally

558-413: The Slickrock Trail was originally laid out in 1969 by Richard R. Wilson for use by Honda Trail 90s (before the mountain bike was invented), and the area is still open to such recreation today. 4X4 and off-road enthusiasts will find a challenge on the nearby Hell's Revenge 4X4 Trail, which intersects the Slickrock Trail in several places. The so-called "slickrock" sandstone , which forms the majority of

589-699: The claims in the patent - incapable of being burned and acquires the features of petrified wood. Some uses of this product as suggested by Hicks include use by horse breeders who desire fireproof stables constructed of nontoxic material that would also be resistant to chewing of the wood by horses. In 2005 scientists at the Pacific Northwest National Laboratory (PNNL) reported that they had successfully petrified wood samples artificially. Unlike natural petrification, though, they infiltrated samples in acidic solutions, diffused them internally with titanium and carbon and fired them in

620-408: The crystals. In silicification , the weathering of rocks releases silicate minerals and the silica makes its way into a body of still water. Eventually, the mineral-laden water permeates the pores and cells of some dead organism, where it becomes a gel . Over time, the gel will dehydrate , forming an opaline crystal structure that is an internal cast of the organism. This accounts for

651-463: The detail found in permineralization. Silicification reveals information about what type of environment the organism was likely to have lived in. Most fossils that have been silicified are bacteria , algae , and other plant life. Silicification is the most common type of permineralization. Carbonate mineralization involves the formation of coal balls. Coal balls are the fossilizations of many different plants and their tissues. They often occur in

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682-416: The elements sulfur and iron . Organisms may become pyritized when they are in marine sediments saturated with iron sulfides. ( Pyrite is iron sulfide.) As organic matter decays it releases sulfide which reacts with dissolved iron in the surrounding waters. Pyrite replaces carbonate shell material due to an undersaturation of carbonate in the surrounding waters. Some plants become pyritized when they are in

713-809: The fossils produced through the process of petrifaction used for paleontological study, but they have also been used as both decorative and informative pieces. Petrified wood is used in several ways. Slabs of petrified wood can be crafted into tabletops, or the slabs themselves are sometimes displayed in a decorative fashion. Also, larger pieces of the wood have been carved into sinks and basins. Other large pieces can also be crafted into chairs and stools. Petrified wood and other petrified organisms have also been used in jewelry, sculpture, clock-making, ashtrays and fruit bowls, and landscape and garden decorations. Petrified wood has also been used in construction. The Petrified Wood Gas Station, located on Main St Lamar, Colorado ,

744-454: The organisms' tissues are filled when these minerals precipitate out of the water. Two common types of permineralization are silicification and pyritization. Silicification is the process in which organic matter becomes saturated with silica . A common source of silica is volcanic material. Studies have shown that in this process, most of the original organic matter is destroyed. Silicification most often occurs in two environments—either

775-552: The presence of seawater or acidic peat. Coal balls are calcareous permineralizations of peat by calcium and magnesium carbonates. Often spherical in shape and ranging from a few grams to several hundred kilograms in mass, coal balls are formed when water containing carbonate permeates the cells of an organism. This type of fossilization yields information about plant life in the Upper Carboniferous Period (325 to 280 million years ago). This method involves

806-407: The specimen are progressively dissolved and silica is deposited into the empty spaces. In wood samples, as the process proceeds, cellulose and lignin, two components of wood, are degraded and replaced with silica. The specimen is transformed to stone (a process called lithification) as water is lost. For silicification to occur, the geothermic conditions must include a neutral to slightly acidic pH and

837-451: The specimen is buried in sediments of deltas and floodplains or organisms are buried in volcanic ash. Water must be present for silicification to occur because it reduces the amount of oxygen present and therefore reduces the deterioration of the organism by fungi, maintains organism shape, and allows for the transportation and deposition of silica. The process begins when a specimen is permeated with an aqueous silica solution. The cell walls of

868-402: The trail's surface has a surface much like sandpaper , making it really grippable by the rubber tires of a mountain bike or off-road motorcycle. The texture is notorious for inflicting severe abrasion injuries. The name "slickrock" was used by early settlers of the area to describe the sandstone because of the low traction between horses' metal shoes and the rock's sloping surfaces. The same

899-561: The trail, becoming lost, or disturbing the fragile cryptobiotic soil near which the trail passes. Trail maintainers also use yellow markings near blind drop-offs, narrow ledges, and other features to indicate to riders where to be particularly careful. [REDACTED] Sports portal 38°34′53″N 109°31′10″W  /  38.581365°N 109.51947°W  / 38.581365; -109.51947 Petrified In geology , petrifaction or petrification (from Ancient Greek πέτρα ( pétra )  'rock, stone')

930-496: The wood material remains to a certain degree; the constituents of wood (cellulose, lignins, lignans, oleoresins, etc.) have not been replaced by silicate, but have been infiltrated by specially formulated acidic solutions of aluminosilicate salts that gel in contact with wood matter and form a matrix of silicates within the wood after being left to react slowly for a given period of time in the solution or heat-cured for faster results. Hamilton Hicks of Greenwich, Connecticut , received

961-641: Was built in 1932 and consists of walls and floors constructed from pieces of petrified wood. The structure, built by W.G. Brown, has since been converted to office space and a used car dealership. Glen Rose, Texas provides even more examples of the use of fossilized wood in architecture. Beginning in the 1920s, the farmers of Somervell County, Texas began uncovering petrified trees. Local craftsmen and masons then built over 65 structures from this petrified wood, 45 of which were still standing as of June 2009. These structures include gas stations, flowerbeds, cottages, restaurants, fountains and gateposts. Glen Rose, Texas

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