HOME
*



picture info

Septaria
A concretion is a hard, compact mass of matter 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 derived from the Latin "(act of) compacting, condensing, congealing, uniting", itself from ''con'' meaning 'together' and ''crescere'' meaning "to grow". 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 ce ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Pseudofossil
Pseudofossils are inorganic objects, markings, or impressions that might be mistaken for fossils. Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures. One common example is when manganese oxides crystallize with a characteristic treelike or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are sometimes thought to be fossils, and occasionally one contains a fossil, but are generally not fossils themselves. Chert or flint nodules in limestone can often take forms that resemble fossils. Background Pyrite disks or spindles are sometimes mistaken for fossils of sand dollars or other forms (see marcasite). Cracks, bumps, gas bubbles, and such can be difficult to distinguish from true fossils. Specimens that cannot be attributed with certainty to either fossils or pseudofossils are treated ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Bowling Balls Beach 2 Edit
Bowling is a target sport and recreational activity in which a player rolls a ball toward pins (in pin bowling) or another target (in target bowling). The term ''bowling'' usually refers to pin bowling (most commonly ten-pin bowling), though in the United Kingdom and Commonwealth countries, bowling could also refer to target bowling, such as lawn bowls. In pin bowling, the goal is to knock over pins on a long playing surface known as a ''lane''. Lanes have a wood or synthetic surface onto which protective lubricating oil is applied in different specified oil patterns that affect ball motion. A strike is achieved when all the pins are knocked down on the first roll, and a spare is achieved if all the pins are knocked over on a second roll. Common types of pin bowling include ten-pin, candlepin, duckpin, nine-pin, and five-pin. The historical game skittles is the forerunner of modern pin bowling. In target bowling, the aim is usually to get the ball as close to a mark as po ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Shell (projectile)
A shell, in a military context, is a projectile whose payload contains an explosive, incendiary, or other chemical filling. Originally it was called a bombshell, but "shell" has come to be unambiguous in a military context. Modern usage sometimes includes large solid kinetic projectiles that is properly termed shot. Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used. All explosive- and incendiary-filled projectiles, particularly for mortars, were originally called ''grenades'', derived from the French word for pomegranate, so called because of the similarity of shape and that the multi-seeded fruit resembles the powder-filled, fragmentizing bomb. Words cognate with ''grenade'' are still used for an artillery or mortar projectile in some European languages. Shells are usually large-caliber projectiles fired by artillery, armored fighting vehicles (e.g. tanks, assault guns, and mortar carriers), warships, and autocannons. The shape ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Aggregate (geology)
In the Earth sciences, aggregate has three possible meanings. In mineralogy and petrology, an aggregate is a mass of mineral crystals, mineraloid particles or rock particles. Examples are dolomite, which is an aggregate of crystals of the 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 mined or quarried for use as a building material. In pedology, an aggregate is a mass of soil particles. If the aggregate has formed naturally, it can be called a ped; if formed artificially, it can be called a clod. Construction aggregate examples * basalt * dolomite * granite * gravel * limestoneSame Day Agg ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Faiyum Depression
The Faiyum Oasis ( ar, واحة الفيوم ''Waḥet El Fayyum'') is a depression or basin in the desert immediately to the west of the Nile, or just 62 miles south of Cairo in 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 rich 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 ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Qasr El Sagha Formation
The Qasr el Sagha Formation is a 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 deltaic to shallow marine environment.Gingerich et al., 2019 It dates to the Late Eocene (middle Priabonian, ). Paleontological significance Fossils of the 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 adequately described before their destruction during the bombing of ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

North Dakota
North Dakota () is a U.S. state in the Upper Midwest, named after the Native Americans in the United States, indigenous Dakota people, Dakota Sioux. North Dakota 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. It is believed to host the geographic center of North America, Rugby, North Dakota, Rugby, and is home to the tallest man-made structure in the Western Hemisphere, the KVLY-TV mast. North Dakota is the List of U.S. states and territories by area, 19th largest state, but with a population of less than 780,000 2020 United States census, as of 2020, it is the List of U.S. states and territories by population, 4th least populous and List of U.S. states by population density, 4th most sparsely populated. The capital is Bismarck, North Dakota, Bismarck while the largest city is Fargo, North Dakota, Fargo, which accounts for nearly a fifth of the s ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Theodore Roosevelt National Park
Theodore Roosevelt National Park is an American national park of the badlands in western North Dakota comprising three geographically separated areas. Honoring U.S. President Theodore Roosevelt, it is the only American national park named directly 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 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 Elkhorn Ranch is located between the North and South units. Both main units of the park have scenic drives, approximately of foot and horse trails, wildlife viewing, and back country hiking and camping. The park received 850,000 recreational visitors in 2021. History Roosevelt connection Roosevelt ...
[...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 Wales * 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, an isl ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sediments
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently 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 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 processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and 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. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain shape, and ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]