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Waldron Shale
The Waldron Shale is a geologic formation in Indiana. It preserves fossils dating back to the Silurian period. These fossils comprise at least three different benthic communities primarily living in the inter-reef, deep waters that were stable for much of the Wenlockian epoch. Many of these fossils are found most frequently around microbioherms constructed by small encrusting organisms which protected other species from the effects of storms. This formation was named by Moses N. Elrod, M.D. in 1883. He wrote about in a report about the geology of Decatur County, Indiana. "The Upper Niagara shale bed, is the calcareous clay, shale and thin strata of limestone overlying the quarry stone, and closing the Niagara period and group. The greater per cent of the mass is carbonate of lime. In Shelby county, they are known as the Waldron beds. In my report on Bartholomew county, I generally called this formation Calcareous shale, which is appropriate so far as chemical composition i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clay is the oldest known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock. Foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression. The foliation in slate is called " slaty cleavage". It is caused by strong compression causing fine grained clay flakes to regrow in planes perpendicular to the compression. When expertly "cut" by striking parallel to the foliation, with a specialized tool in the quarry, many slates will display a property called fissility, forming smooth flat sheets of stone which have long been used for roofing, floor tiles, and other purposes. Slate is frequently grey in color, especially when seen, en masse, covering roofs. However, slate occurs in a variety of colors even from a single locality; f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamination (geology)
In geology, lamination () is a small-scale sequence of fine layers (laminae; singular: lamina) that occurs in sedimentary rocks. Laminae are normally smaller and less pronounced than bedding. Lamination is often regarded as planar structures one centimetre or less in thickness, whereas bedding layers are greater than one centimetre. However, structures from several millimetres to many centimetres have been described as laminae. A single sedimentary rock can have both laminae and beds. Description Lamination consists of small differences in the type of sediment that occur throughout the rock. They are caused by cyclic changes in the supply of sediment. These changes can occur in grain size, clay percentage, microfossil content, organic material content or mineral content and often result in pronounced differences in colour between the laminae. Weathering can make the differences even more clear. Lamination can occur as parallel structures (parallel lamination) or in different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waldron, Indiana
Waldron is an unincorporated community and census-designated place in Liberty Township, Shelby County, in the U.S. state of Indiana. History Waldron was originally called Stroupville, and under that name was laid out in 1854 by George Stroup, and named for him. The residents were later unsatisfied with the original name, and petitioned to have it changed to Waldron. The first post office in the community was called Conns Creek. The post office was established in 1832 and was renamed Waldron in 1876, where it is still operating. Geography Waldron is located at . Climate The climate in this area is characterized by hot, humid summers and generally mild to cool winters. According to the Köppen Climate Classification system, Waldron has a humid subtropical climate A humid subtropical climate is a zone of climate characterized by hot and humid summers, and cool to mild winters. These climates normally lie on the southeast side of all continents (except Antarctica), generally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bartholomew County, Indiana
Bartholomew County is a county located in the U.S. state of Indiana. The population was 82,208 at the 2020 census. The county seat is Columbus. The county was determined by the U.S. Census Bureau to be home to the mean center of U.S. population in 1900. Bartholomew County makes up the Columbus, Indiana Metropolitan Statistical Area, which is part of the Indianapolis-Carmel-Muncie Combined Statistical Area. History Bartholomew County was formed on February 12, 1821, and was named for Lt. Col. Joseph Bartholomew, wounded at the Battle of Tippecanoe. The site of the county seat was chosen on February 15, 1821, by a team of commissioners, who suggested the name Tiptona, in honor of John Tipton. Courthouse The current Bartholomew County courthouse was built from 1870 to 1874 by McCormack and Sweeney of Columbus at a cost of $225,000. It was designed by architect Isaac Hodgson, who was born in Belfast, Ireland in 1826 and immigrated to the United States in 1848; he designed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shelby County, Indiana
Shelby County is a county in the U.S. state of Indiana. As of the 2010 United States Census, the population was 44,436. The county seat (and only incorporated city) is Shelbyville. History After the American Revolutionary War established US sovereignty over the territory of the upper midwest, the new federal government defined the Northwest Territory in 1787, which included the area of present-day Indiana. In 1800, Congress separated Ohio from the Northwest Territory, designating the rest of the land as the Indiana Territory. President Thomas Jefferson chose William Henry Harrison as the governor of the territory, and Vincennes was established as the capital. After the Michigan Territory was separated and the Illinois Territory was formed, Indiana was reduced to its current size and geography. By December 1816 the Indiana Territory was admitted to the Union as a state. The Native people who inhabited these areas prior to arrival of European settlers were generally resistant t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable bed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically about such structures as the operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate tests of often more or less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous, as are calcareous sponges (Porifera), that have spicules which are made of calcium carbonate. In botany ''Calcareous grassland'' is a form of grassland characteristic of soils containing much calcium carbonate from underlying chalk or limestone rock. In medicine The term is used in pathology, for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decatur County, Indiana
Decatur County is a county in the U.S. state of Indiana. As of the 2020 United States Census, the population was 26,472. The county seat (and only incorporated city) is Greensburg. History In 1787, the US defined the Northwest Territory which included the area of present-day Indiana. In 1800, Congress separated Ohio from the Northwest Territory, designating the rest of the land as the Indiana Territory. President Thomas Jefferson chose William Henry Harrison as the governor of the territory, and Vincennes was established as the capital. After the Michigan Territory was separated and the Illinois Territory was formed, Indiana was reduced to its current size and geography. By December 1816 the Indiana Territory was admitted to the Union as a state. Starting in 1794, Native American titles to Indiana lands were extinguished by usurpation, purchase, or war and treaty. The United States acquired land from the Native Americans in the 1809 treaty of Fort Wayne, and by the treaty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
