What is a magmatic ore deposit?
Magmatic ore deposits are derived from accumulations of crystals of metallic oxides, or immiscible sulfide, or oxide liquids that formed during the cooling and crystallization of magma, typically with mafic to ultramafic compositions.
What is ore deposit meaning?
An ore deposit, in its simplest terms, is a portion of the Earth’s crust from which some industrial raw material can be extracted at a profit. As such, its characteristics are as much economic as geochemical.
Where are magmatic ore deposits?
Summary. Magmatic ore deposits, also known as orthomagmatic ore deposits, are deposits within igneous rocks or along their contacts in which ore minerals crystallised from a melt or were transported in a melt.
What is supergene deposit?
In ore deposit geology, supergene processes or enrichment are those that occur relatively near the surface as opposed to deep hypogene processes. Supergene processes include the predominance of meteoric water circulation (i.e. water derived from precipitation) with concomitant oxidation and chemical weathering.
What minerals form in magmatic ore deposits?
Three oxide ore minerals form magmatic cumulates: chromite, magnetite, and ilmenite.
How a magmatic mineral deposit is formed?
When magma or lava cools, the magma and ore carried within it crystallize to form tiny minerals in the newly-created igneous rock. Minerals found in such rock might include feldspar or mica. Minerals can also be transported and released from water sources, such as seawater, river water, or groundwater.
What is supergene and hypogene?
Supergene is a term used to describe near-surface processes and their products, formed at low temperature and pressure by the activity of descending water and gas. The opposite term is hypogene, formed by ascending water and gas at high temperature and pressure.
What causes ore deposits?
Deposits of minerals form when a medium that contains and transports mineral-making ore releases and deposits the ore. Magma is one such medium that transports ores. When magma or lava cools, the magma and ore carried within it crystallize to form tiny minerals in the newly-created igneous rock.
How are ore deposits found?
To find a mineral deposit, geologists study the geology of a lot of places. They then go to a spot where that type of mineral deposit could be found. They test the properties of the soil and rocks. They look at the chemistry and the physical properties.
What is supergene ore?
In the traditional view, supergene ore and gangue minerals are the products of reactions between hypogene sulfide minerals and descending, acidic meteoric waters; these processes take place at or near the ground surface in subaerial environments (Guilbert and Park, 1986).
What is hypogene deposit?
Hypogene ore deposits are formed under the influence of deep-seated endogene (=hypogene) geologic processes by the action of ascending solutions. Such solutions and conditions of ore formation are also called hypogene. The temperature and pressure are higher in hypogene than in supergene conditions.
What is an example of a magmatic ore deposit?
Magmatic Ore Deposits: A number of processes that occur during cooling and crystallization of magmatic bodies can lead to the separation and concentration of minerals. 1-Pegmatites 2-Layered intrusions 3-Kimberlites Examples of Magmatic ore deposits: 1-Chromite deposits 2-Nickel ŒCopper deposits 3-Platinum group metal (PGM) deposits
What is an ore deposit?
What is an ore deposit? Magmatic ore deposits, also known as orthomagmatic ore deposits, are deposits within igneous rocks or along their contacts in which ore minerals crystallised from a melt or were transported in a melt.
What are magmatic-hydrothermal ore deposits?
Magmatic-hydrothermal ore deposits are hydrothermal ore deposits in which the aqueous solutions were derived from magma. These ore deposits are described further in Chapter 3.
What is a hydrothermal ore deposit?
Ore deposits that form in and around igneous rock units as a result of mineral precipitation from aqueous solutions or hydrothermal fluids are hydrothermal ore deposits. Magmatic-hydrothermal ore deposits are hydrothermal ore deposits in which the aqueous solutions were derived from magma.