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Realgar

Realgar is a mineral. Its chemical formula is As 4 S 4. It is a soft red mineral. It is an ore of arsenic. It changes into a yellow powder when exposed to light. This yellow powder is called pararealgar. It melts at 320°C and burns with a blue fl ...

                                               

Ringwoodite

Ringwoodite is a mineral. It is a type of olivine which is formed at high temperatures and pressures in the Earths mantle between 525 and 660 km deep. Olivine is a magnesium iron silicate. This mineral was first identified in a meteorite in 1969. ...

                                               

Salar de Uyuni

Salar de Uyuni is the worlds largest salt flat. It is over 10.000 square kilometres in area. It is in Potosi in southwest Bolivia, near the crest of the Andes at an height of 3.656 metres 11.995 ft above sea level. The crust serves as a source of ...

                                               

Tellurite

Tellurite is an ion. Its chemical formula is TeO 3 2-. They are some of the more stable tellurium compounds. They are weak oxidizing agents. In slightly acidic conditions, it makes hydrogen tellurite, HTeO 3 -. When it is very acidic, it makes te ...

                                               

Vermiculite

Vermiculite is a phyllosilicate mineral that is dug out of the ground in China, South Africa, Russia and Brazil. When it is dug from the ground it is a hard rock. Vermiculite gets bigger when it is heated and changes into a material that looks li ...

                                               

2010 Copiapo mining accident

The 2010 Copiapo mining accident was a mining accident that happened on August 5, 2010, when the copper-gold mine of San Jose, near Copiapo, Chile, collapsed. It left 33 miners trapped around 700 meters under the ground. The Mine of San Jose Mina ...

                                               

Camborne

Camborne is a town in west Cornwall, England, United Kingdom. It is at the western edge of a conurbation consisting of Camborne, Pool and Redruth. The population of Camborne was 20.010 at the 2001 census. The population of the whole conurbation w ...

                                               

Gravel

Gravel is small, loose, rock particles. It is any loose rock that is larger than 2 mm in its smallest dimension and no more than 64 mm. Small gravel is composed of granules > 2 to 4 mm/0.079 to 0.16 in. Large gravel is called pebbles > 4 to ...

                                               

Indooroopilly Silver Mine

In 1918, G. Olsen and his neighbour, Patrick J. Madden discovered silver-lead traces on Mr Olsen’s land at Finney’s Hill, Indooroopilly, a suburb of Brisbane, Queensland, 10km from the city centre. After some promising excavations all over the pr ...

                                               

James Wilson Marshall

James Wilson Marshall was an American carpenter and sawmill worker. He reported finding gold at Coloma on the American River in California on January 24, 1848. This started the California Gold Rush. The mill was owned by John Sutter. Marshall had ...

                                               

Mining in Kutna Hora

In the Middle Ages, Kutna Hora belonged to one of the most important cities in the Bohemian Kingdom. The silver mining started in the second half of 13th century. Unfortunately, the exact date and place, where it all started, remains unknown. Bec ...

                                               

Rio Tinto

Rio Tinto Group is the worlds second largest metals and mining corporation. It is mainly active in mining. It produces iron ore, copper, diamonds, gold and uranium. The company was founded in 1873, when a consortium of investors bought a mine com ...

                                               

Rock of Ages Corporation

Rock of Ages Corporation is a company in Vermont. It mines granite, which it sells largely for use in memorials, though it also makes smaller products. It was started in 1885, and has its headquarters in Graniteville, Vermont, which is close to B ...

                                               

Surface mining

Surface mining is a method which operates on the surface of the land. Machines remove the overburden to get at material, such as coal, below it. Surface mining includes strip mining, open-pit mining UK: open cast mining and mountaintop removal mi ...

                                               

Uranium mining

Uranium mining takes uranium ore from the ground for processing. Kazakhstan, Canada, and Australia are the top three producers and together account for 64% of world uranium production. Uranium from mining is mostly used as fuel for nuclear power ...

                                               

LAtalante basin

The LAtalante basin is a very salty lake at the bottom of the Mediterranean Sea. 35.18°N 21.41°E  / 35.18; 21.41 It is about 190 km ~120 miles west of the island of Crete. It is called a lake because, though it is under more than two miles of wa ...

                                               

Mariana Trench

The Mariana Trench is the deepest known submarine trench. It is also the deepest known location on Earth itself. It lies south and east of the Mariana Islands, and has a depth up to 10.971 m. The western end of the trench is near Guam. The trench ...

                                               

Mediterranean Ridge

The Mediterranean Ridge is a wide ridge in the floor of the Mediterranean Sea. It is next to a rough quarter circle from Calabria, south of Crete, to the southwest corner of Turkey, and from there eastwards south of Turkey, with Cyprus. From what ...

                                               

Ocean gyre

A gyre is a large system of ocean currents moving in a circle. Gyres are caused by the Coriolis effect. Because the Earth is rotating, ocean currents in the northern hemisphere tend to move in a clockwise direction and currents in the southern he ...

                                               

Ocean surface wave

Ocean surface waves are surface waves that occur in the upper layer of the ocean. They usually result from wind. Some are made by geologic effects like earthquakes or vulcanicity and may travel thousands of miles before striking land. They range ...

                                               

Seafloor spreading

Seafloor spreading happens at the bottom of an ocean as tectonic plates move apart. The seafloor moves and carries continents with it. At ridges in the middle of oceans, new oceanic crust is created. The motivating force for seafloor spreading ri ...

                                               

Tide

A tide is the periodic rising and falling of Earths ocean surface caused mainly by the gravitational pull of the Moon acting on the oceans. Tides cause changes in the depth of marine and estuarine waters. Tides also make oscillating currents know ...

                                               

Waves at shallow water

Waves at shallow water develop when the ocean surface waves travel into the coastal area where the wavelength is much larger than the water depth. The normal circular motion of the water particles there is disrupted by the ocean bottom. As the wa ...

                                               

Rock (geology)

A rock is a naturally occurring solid. It is made of minerals, or other mineral-like substances. The Earths outer solid layer, the lithosphere, is made of rock. That means the Earths crust is made of rock. The different minerals in the rocks make ...

                                               

Bauxite

Bauxite is the main ore of aluminium. It is mostly aluminium oxide. Bauxite is the most important aluminium ore. It is largely made up of the minerals Gibbsite AlOH 3, Boehmite γ-AlOOH, and Diaspore α-AlOOH, together with the iron oxides Goethite ...

                                               

Dyke (geology)

A dyke in geology is a type of later vertical rock between older layers of rock. Technically, it is any geologic body which cuts across: a) flat wall rock structures, such as bedding. b) massive rock formations, usually igneous in origin. Dikes c ...

                                               

Igneous rock

Igneous rock is one of the three main rock types, the others being sedimentary and metamorphic rock. Igneous rocks are rocks formed from molten magma. The material is made liquid by the heat inside the Earths mantle. When magma comes out onto the ...

                                               

Mafic

Mafic is an adjective describing a silicate mineral or igneous rock which is rich in magnesium and iron. The term is a portmanteau, made up from "magnesium" and "ferric". Mafic minerals are usually dark in color and have a specific gravity greate ...

                                               

Metamorphic rock

A metamorphic rock is a type of rock which has been changed by extreme heat and pressure. Its name is from morph, and meta. The original rock gets heated temperatures greater than 150 to 200 °C and pressured 1500 bars. This causes profound physic ...

                                               

Stratigraphy

Stratigraphy is a branch of geology which studies rock formations called strata. It is important in the study of sedimentary and layered vocanic rocks.

                                               

Sedimentology

Sedimentology is the study of sediments such as sand, mud, and clay. How they are laid down today is used to understand how rocks were formed. Sedimentologists use their understanding of modern processes to interpret sedimentary rocks and sedimen ...

                                               

Sediment

Sediment is made of small particles deposited in water or on land. After deposition, sediments may stay in their new place a long time and be covered by newer sediments. Pressure may slowly transform sediment into sedimentary rocks. The word sedi ...

                                               

Sedimentary rock

Sedimentary rocks are rocks formed from sediment. They are deposited over time, and often show layers which can be seen in cliffs. Other types of rock are igneous rock and metamorphic rock. Sediments are usually formed from matter which falls to ...

                                               

Soil science

Soil science deals with soil as a natural resource on the surface of the earth. It includes soil formation, classification and mapping. But many more sciences deal with knowledge of soils and the advancement of the soil sciences: engineering, agr ...

                                               

Rhythmite

A rhythmite is layers of sediment or sedimentary rock laid down in a repeated pattern. This pattern may be varves, which are an annual pattern, or shorter or longer-term rhymites. Tides in some places have left rhythmites.

                                               

Unconformity

An unconformity is a gap in the sequence of rocks in a geologic column. It is a buried erosion surface separating two rock strata of different ages. It shows that sediment deposition was broken for a time, usually because the land was above sea l ...

                                               

Flood basalt

A flood basalt or trap basalt is the result of a giant volcanic eruption or series of eruptions that coats large stretches of land or the ocean floor with basalt lava. Flood basalts have covered areas as large as a continent in prehistory, creati ...

                                               

Lava

Lava is magma, hot molten rock that flows through holes in the Earths crust and onto the surface. Like magma, lava can be either viscous or fluid. Blocky lava is so thick and slow that it barely moves along the ground. Other types of lava, like p ...

                                               

Magma

Magma is the melted rock under the ground. There are different types of magma. One is called felsic magma. Felsic magma is thick and has silica minerals. It mostly makes light-coloured rocks. Another type is called mafic magma, which is runny and ...

                                               

Plinian eruption

A Plinian eruption is a kind of volcanic eruption which is similar to that of Mount Vesuvius in the year 79 AD. It is named after Pliny the Younger who wrote the only surviving eyewitness account of the eruption. That eruption of Vesuvius killed ...

                                               

Supervolcano

A supervolcano is a volcano that can make a volcanic eruption where the things being thrown out of the volcano have a volume bigger than 1.000 km 3. This is thousands of times bigger than most volcanic eruptions which happened a long time. Superv ...

                                               

Volcanic eruption

A volcanic eruption occurs when hot materials from the Earths interior are thrown out of a volcano. Lava, rocks, dust, and gas compounds are some of these "ejecta". Eruptions can come from side branches or from the top of the volcano. Some erupti ...

                                               

Volcanism

Volcanism is the eruption of magma onto the surface of the Earth. Magma under the crust is under very great pressure. When folding and faulting occur, cracks or fractures appear. These are lines of weakness. When these lines of weakness develop d ...

                                               

Conservation law

A conservation law is a statement used in physics that says that the amount of something does not change in time. That thing could be as simple as mass or charge, or something that has to be calculated, like energy, or angular momentum. For examp ...

                                               

Convection

Convection is the movement of heat because of the movement of warm matter. For example, atmospheric circulation moves warm air to cool places, causing wind. Wind, in turn, can enter and cool a room if the window is open. The movement of the cloud ...

                                               

Eigenvalues and eigenvectors

Linear algebra talks about types of functions called transformations. In that context, an eigenvector is a vector - different from the null vector - which does not change direction after the transformation. The vector may change its length, or be ...

                                               

Electron

An electron is a very small piece of matter and energy. Its symbol is e −. It was discovered by J. J.Thomson in 1897. The electron is a subatomic particle. It is believed to be an elementary particle because it cannot be broken down into anything ...

                                               

Elementary particle

In physics, an elementary particle or fundamental particle is a particle that is not made of other particles. An elementary particle can be one of two groups: a fermion or a boson. Fermions are the building blocks of matter and have mass, while b ...

                                               

Field (physics)

In physics, a field means that a physical quantity is assigned to every point in space. A field is seen as extending throughout a large region of space so that it influences everything. The strength of a field usually varies over a region. Michae ...

                                               

Heat conduction

Heat conduction is the movement of heat from one object to another one that has different temperature when they are touching each other. For example, we can warm our hands by touching hot-water bottles. When the cold hands touch the hot-water bot ...