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Calcite Rafts
Calcite crystals form on the surface of quiescent bodies of water, even when the bulk water is not supersaturated with respect to calcium carbonate. The crystals grow, attach to one other and appear to be floating rafts of a white, opaque material. The floating materials have been referred to as calcite rafts or "leopard spots". Chemistry Calcium carbonate is known to precipitate as calcite crystals in water supersaturated with calcium and carbonate ions. Under quiescent conditions, calcite crystals can form on a water surface when calcium carbonate supersaturation conditions do not exist in the bulk water. Water evaporates from the surface and carbon dioxide degasses from the surface layer to create a thin layer of water with high pH and concentrations of calcium and carbonate ions far above the saturation concentration for calcium carbonate. Calcite crystals precipitate in this highly localized environment and attach to one another to form what appear to be rafts of a whit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leopard Spot1
The leopard (''Panthera pardus'') is one of the five extant species in the genus ''Panthera'', a member of the cat family, Felidae. It occurs in a wide range in sub-Saharan Africa, in some parts of Western and Central Asia, Southern Russia, and on the Indian subcontinent to Southeast and East Asia. It is listed as Vulnerable on the IUCN Red List because leopard populations are threatened by habitat loss and fragmentation, and are declining in large parts of the global range. The leopard is considered locally extinct in Hong Kong, Singapore, South Korea, Jordan, Morocco, Togo, the United Arab Emirates, Uzbekistan, Lebanon, Mauritania, Kuwait, Syria, Libya, Tunisia and most likely in North Korea, Gambia, Laos, Lesotho, Tajikistan, Vietnam and Israel. Contemporary records suggest that the leopard occurs in only 25% of its historical global range. Compared to other wild cats, the leopard has relatively short legs and a long body with a large skull. Its fur is marked with rosettes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpinteria, California
Carpinteria (; es, Carpintería, meaning "Carpentry") is a small seaside city in southeastern Santa Barbara County, California. Located on the Central Coast (California), Central Coast of California, it had a population of 13,264 at the 2020 United States Census, 2020 census. Carpinteria is a popular surf destination; the city embraced the slogan "World's Safest Beach" in 1912, which it still uses today. History Carpinteria was home to a Chumash people, Chumash village during pre-colonial times, which was known as Šujtu. In 1769, the Spanish Portolá expedition came west along the beach from the previous night's encampment at Rincon (surfspot), Rincon. The explorers found a large native village on the point of land where Carpinteria Pier is today. The party camped nearby on Timeline of the Portolá expedition, August 17. Fray Juan Crespí, a Franciscan missionary travelling with the expedition, noted that "Not far from the town we saw some springs of pitch. The Indians have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kartchner Caverns
Kartchner Caverns State Park is a state park of Arizona, United States, featuring a show cave with of passages. The park is located south of the town of Benson and west of the north-flowing San Pedro River. Long hidden from view, the caverns were discovered in 1974 by local cavers, assisted by state biologist Erick Campbell who helped in its preservation. The park encompasses most of a down-dropped block of Palaeozoic rocks on the east flank of the Whetstone Mountains. The caverns are carved out of limestone and filled with spectacular speleothems which have been growing for 50,000 years or longer, and are still growing. Careful and technical cave state park development and maintenance are designed to preserve the cave system. History The caverns were discovered in 1974, when cavers Gary Tenen and Randy Tufts found a narrow crack in the bottom of a sinkhole, and followed the source of warm, moist air toward what ended up being more than of pristine cave passages. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flowstone
Flowstones are sheetlike deposits of calcite or other carbonate minerals, formed where water flows down the walls or along the floors of a cave. They are typically found in "solution caves", in limestone, where they are the most common speleothem. However, they may form in any type of cave where water enters that has picked up dissolved minerals. Flowstones are formed via the degassing of vadose percolation waters. Flowstone may also form on manmade structures as a result of calcium hydroxide being leached from concrete, lime or mortar. These secondary deposits created outside the cave environment, which mimic the shapes and forms of speleothems, are classified as "calthemites" and are associated with concrete degradation.Smith, G.K., (2016). “Calcite Straw Stalactites Growing From Concrete Structures”, Cave and Karst Science, Vol.43, No.1, P.4-10, (April 2016), British Cave Research Association, ISSN 1356-191X. Formation Flowing films of water that move along floors or do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stalagmite
A stalagmite (, ; from the Greek , from , "dropping, trickling") is a type of rock formation that rises from the floor of a cave due to the accumulation of material deposited on the floor from ceiling drippings. Stalagmites are typically composed of calcium carbonate, but may consist of lava, mud, peat, pitch, sand, sinter, and amberat (crystallized urine of pack rats). The corresponding formation hanging down from the ceiling of a cave is a stalactite. Mnemonics have been developed for which word refers to which type of formation; one is that ''stalactite'' has a C for "ceiling", and ''stalagmite'' has a G for "ground", another is that, as with ants in the pants, the mites go up and the tights (tites) come down. Formation and type Limestone stalagmites The most common stalagmites are speleothems, which usually form in limestone caves. Stalagmite formation occurs only under certain pH conditions within the cavern. They form through deposition of calcium carbonate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leachate
A leachate is any liquid that, in the course of passing through matter, extracts soluble or suspended solids, or any other component of the material through which it has passed. Leachate is a widely used term in the environmental sciences where it has the specific meaning of a liquid that has dissolved or entrained environmentally harmful substances that may then enter the environment. It is most commonly used in the context of land-filling of putrescible or industrial waste. In the narrow environmental context leachate is therefore any liquid material that drains from land or stockpiled material and contains significantly elevated concentrations of undesirable material derived from the material that it has passed through. Landfill leachate Leachate from a landfill varies widely in composition depending on the age of the landfill and the type of waste that it contains. It usually contains both dissolved and suspended material. The generation of leachate is caused principally b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleothem
A speleothem (; ) is a geological formation by mineral deposits that accumulate over time in natural caves. Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take a variety of forms, depending on their depositional history and environment. Their chemical composition, gradual growth, and preservation in caves make them useful paleoclimatic proxies. Chemical and physical characteristics More than 300 variations of cave mineral deposits have been identified. The vast majority of speleothems are calcareous, composed of calcium carbonate (CaCO3) minerals (calcite or aragonite). Less commonly, speleothems are made of calcium sulfate (gypsum or mirabilite) or opal. Speleothems of pure calcium carbonate or calcium sulfate are translucent and colorless. The presence of iron oxide or copper provides a reddish brown color. The presence of manganese oxide can create darker colors such as black or dark brown. Speleothems can also be brown d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread illegal sand mining, impacts on the surrounding environment such as increased surface runoff or urban heat island effect, and potential public health implications from toxic ingredients. Significant research and development is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calthemite
Calthemite is a secondary deposit, derived from concrete, lime, mortar or other calcareous material outside the cave environment.Smith, G.K. (2016). "Calcite straw stalactites growing from concrete structures", Cave and Karst Science 43(1), 4–10. http://bcra.org.uk/pub/candks/index.html?j=127Smith, G K., (2015). "Calcite Straw Stalactites Growing From Concrete Structures". Proceedings of the 30th 'Australian Speleological Federation' conference, Exmouth, Western Australia, edited by Moulds, T. pp 93 -108 Calthemites grow on or under, man-made structures and mimic the shapes and forms of cave speleothems, such as stalactites, stalagmites, flowstone etc.Hill, C A and Forti, P, (1997). Cave Minerals of the World, Second Edition. untsville, Alabama: National Speleological Society Inc. Calthemite is derived from the Latin ''calx'' (genitive ''calcis'') "lime" + Latin < Greek ''théma'', "deposit" meaning ‘something laid down’, (also Mediaeval Latin ''thema'', "deposit") and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as ''speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stalactite
A stalactite (, ; from the Greek 'stalaktos' ('dripping') via ''stalassein'' ('to drip') is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble and that can be deposited as a colloid, or is in suspension, or is capable of being melted, may form a stalactite. Stalactites may be composed of lava, minerals, mud, peat, pitch, sand, sinter, and amberat (crystallized urine of pack rats). A stalactite is not necessarily a speleothem, though speleothems are the most common form of stalactite because of the abundance of limestone caves. The corresponding formation on the floor of the cave is known as a stalagmite. Mnemonics have been developed for which word refers to which type of formation; one is that ''stalactite'' has a C for "ceiling", and ''stalagmite'' has a G for "ground". Another example is that ''stalactites'' "hang on ''T''ight" and ''stalagmites'' "''M''ight grow up" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Quality
Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through treatment of the water, can be assessed. The most common standards used to monitor and assess water quality convey the health of ecosystems, safety of human contact, extend of water pollution and condition of drinking water. Water quality has a significant impact on water supply and oftentimes determines supply options. Categories The parameters for water quality are determined by the intended use. Work in the area of water quality tends to be focused on water that is treated for potability, industrial/domestic use, or restoration (of an environment/ecosystem, generally for health of human/aquatic life). Human consumption Contaminants that may be in untreated water include microorganisms such as viruses, protozoa and bacteria; inorganic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
