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Septaria
A concretion is a hard and compact mass formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary rock or soil. Concretions are often ovoid or spherical in shape, although irregular shapes also occur. The word ''concretion'' is borrowed from Latin , itself derived from ''concrescere'' , from ''con-'' and ''crescere'' . Concretions form within layers of sedimentary strata that have already been deposited. They usually form early in the burial history of the sediment, before the rest of the sediment is hardened into rock. This concretionary cement often makes the concretion harder and more resistant to weathering than the host stratum. There is an important distinction to draw between concretions and nodules. Concretions are formed from mineral precipitation around some kind of nucleus while a nodule is a replacement body. Descriptions dating from the 18th century attest to the fact that concretions have long been regarded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregate (geology)
In the Earth sciences, aggregate has three possible meanings. In mineralogy Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical mineralogy, optical) properties of minerals and mineralized artifact (archaeology), artifacts. Specific s ... and petrology, an aggregate is a mass of mineral crystals, mineraloid particles or Rock (geology), rock particles. Examples are Dolomite (rock), dolomite, which is an aggregate of crystals of the mineral dolomite (mineral), dolomite, and ''rock gypsum'', an aggregate of crystals of the mineral gypsum. Lapis lazuli is a type of rock composed of an aggregate of crystals of many minerals including lazurite, pyrite, phlogopite, calcite, potassium feldspar, wollastonite and some sodalite group minerals. In the construction industry, an aggregate (often referred to as a construction aggregate) is sand, gravel or crushed rock that has been mining, mined or Q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Faiyum Depression
The Faiyum Oasis ( ''Wāḥat al-Fayyum'') is a depression or basin in the desert immediately west of the Nile river, 62 miles south of Cairo, Egypt. The extent of the basin area is estimated at between 1,270 km2 (490 mi2) and 1,700 km2 (656 mi2). The basin floor comprises fields watered by a channel of the Nile, the Bahr Yussef, as it drains into a desert hollow to the west of the Nile Valley. The Bahr Yussef veers west through a narrow neck of land north of Ihnasya, between the archaeological sites of El Lahun and Gurob near Hawara; it then branches out, providing agricultural land in the Faiyum basin, draining into the large saltwater Lake Moeris (Birket Qarun). In prehistory it was a freshwater lake, but is today a saltwater lake. It is a source for tilapia and other fish for the local area. Differing from typical oases, whose fertility depends on water obtained from springs, the cultivated land in the Faiyum is formed of Nile mud brought by the Bahr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qasr El Sagha Formation
The Qasr el Sagha Formation is a formation (geology), geological formation located in Egypt. The formation is part of the Wadi El Hitan World Heritage Site. The Qasr el Sagha Formation overlies the Birket Qarun Formation and is overlain by the Gebel Qatrani Formation. The sandstones and shales of the formation were deposited in a river delta, deltaic to shallow marine depositional environment, environment.Gingerich et al., 2019 It dates to the Late Eocene (middle Priabonian, ). Paleontological significance Fossils of the Archaeoceti, early whale genus ''Saghacetus'' ("Sagha whale", originally named "''Zeuglodon osiris''") were first collected at Qasr al Sagha by German explorer Georg August Schweinfurth in January 1886 (a well-preserved dentary).''Saghacetus'' is common in the middle of Qasr el Sagha, but there are few other specimens of archaeocetes whales; the only exception being the enigmatic "''Prozeuglodon stromeri''", named in 1828 based on specimens from 1904, but never ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Dakota
North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, South Dakota to the south, and Montana to the west. North Dakota is part of the Great Plains region, characterized by broad prairies, steppe, temperate savanna, badlands, and farmland. North Dakota is the List of U.S. states and territories by area, 19th-largest state by area, but with a population of just under 800,000, the List of U.S. states and territories by population, fourth-least populous and List of U.S. states by population density, fourth-least densely populated. The List of capitals in the United States, state capital is Bismarck, North Dakota, Bismarck and the List of cities in North Dakota, most populous city is Fargo, North Dakota, Fargo, which accounts for nearly a fifth of the state's population; both cities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodore Roosevelt National Park
Theodore Roosevelt National Park is a List of national parks of the United States, national park of the United States in the badlands of western North Dakota comprising three geographically separated areas. This park pays homage to the time that Theodore Roosevelt spent in the surrounding area and in the Dakota Territories before they were states. Roosevelt lived in the area after his mother and wife died hours apart on February 14, 1884. Theodore Roosevelt National Park is the only American national park named after a single person. The park covers of land in three sections: the North Unit, the South Unit, and the Elkhorn Ranch Unit. The Little Missouri River (North Dakota), Little Missouri River flows through all three units of the park. The Maah Daah Hey Trail connects all three units. The park's larger South Unit lies alongside Interstate 94 near Medora, North Dakota. The smaller North Unit is situated about 80 mi (130 km) north of the South Unit, and Roosevelt's E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock Concretions From Hells Hollow State Park, Pennsylvania
Rock most often refers to: * Rock (geology), a naturally occurring solid aggregate of minerals or mineraloids * Rock music, a genre of popular music Rock or Rocks may also refer to: Places United Kingdom * Rock, Caerphilly, a location in Wales * Rock, Cornwall, a village in England * Rock, County Tyrone, a village in Northern Ireland * Rock, Devon, a location in England * Rock, Neath Port Talbot, a location in Wales * Rock, Northumberland, a village in England * Rock, Somerset, a location in England * Rock, West Sussex, a hamlet in Washington, England * Rock, Worcestershire, a village and civil parish in England United States * Rock, Kansas, an unincorporated community * Rock, Michigan, an unincorporated community * Rock, West Virginia, an unincorporated community * Rock, Rock County, Wisconsin, a town in southern Wisconsin * Rock, Wood County, Wisconsin, a town in central Wisconsin Elsewhere * Corregidor, an island in the Philippines also known as "The Rock" * Jamaica, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediments
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Marsh
A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is dominated by dense stands of salt-tolerant plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh in trapping and binding sediments. Salt marshes play a large role in the aquatic food web and the delivery of nutrients to coastal waters. They also support terrestrial animals and provide coastal protection. Salt marshes have historically been endangered by poorly implemented coastal management practices, with land reclaimed for human uses or polluted by upstream agriculture or other industrial coastal uses. Additionally, sea level rise caused by climate change is endangering other marshes, through erosion and submersion of otherwise tidal marshes. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
