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  2. Layered intrusion - Wikipedia

    en.wikipedia.org/wiki/Layered_intrusion

    A layered intrusion is a large sill -like body of igneous rock which exhibits vertical layering or differences in composition and texture. These intrusions can be many kilometres in area covering from around 100 km 2 (39 sq mi) to over 50,000 km 2 (19,000 sq mi) and several hundred metres to over one kilometre (3,300 ft) in thickness. [1]

  3. Magmatism - Wikipedia

    en.wikipedia.org/wiki/Magmatism

    Magmatism. Geological map showing the Gangdese batholith, which is a product of magmatic activity about 100 million years ago. Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet, which solidifies as igneous rocks. It does so through magmatic activity or igneous activity, the production ...

  4. Ultramafic rock - Wikipedia

    en.wikipedia.org/wiki/Ultramafic_rock

    Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta -igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are usually composed of greater than 90% mafic minerals (dark colored, high magnesium and iron content).

  5. Cumulate rock - Wikipedia

    en.wikipedia.org/wiki/Cumulate_rock

    Secondly, large ultramafic intrusions are rarely sealed systems and may be subject to regular injections of fresh, primitive magma, or to loss of volume due to further upward migration of the magma (possibly to feed volcanic vents or dyke swarms). In such cases, calculating magma chemistries may resolve nothing more than the presence of these ...

  6. Windimurra intrusion - Wikipedia

    en.wikipedia.org/wiki/Windimurra_intrusion

    Setting. The Windimurra Igneous Complex is part of the c. 2813 Ma Meeline Suite of mafic-ultramafic layered intrusions of the central Murchison Domain, Yilgarn Craton of Western Australia. [1] It is a conical body, approximately 7 km thick, primarily composed of layered gabbroic rocks, which intrude into c. 2820 Ma Norie Group rocks of the ...

  7. Great Dyke - Wikipedia

    en.wikipedia.org/wiki/Great_Dyke

    The Great Dyke is a strategic economic resource with significant quantities of chrome and platinum. Chromite occurs to the base of the Ultramafic Sequence and is mined throughout the dyke. [ 4 ] Below the Ultramafic-Mafic sequences' contact, and in the uppermost pyroxenite (bronzitite and websterite) units are economic concentrations of nickel ...

  8. Bushveld Igneous Complex - Wikipedia

    en.wikipedia.org/wiki/Bushveld_Igneous_Complex

    The Bushveld Igneous Complex (BIC) is the largest layered igneous intrusion [ 1 ][ 2 ] within the Earth's crust. [ 3 ] It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin: the Transvaal Basin. It is approximately two billion years old [ 4 ] and is divided into four limbs: northern ...

  9. Stillwater igneous complex - Wikipedia

    en.wikipedia.org/wiki/Stillwater_igneous_complex

    Ore grade is about 2.5 ounces of Pd-Pt per ton of rock, with a Pd-Pt ratio of about 3:1. The Stillwater igneous complex is a large layered mafic intrusion (LMI) located in southern Montana in Stillwater, Sweet Grass and Park Counties. The complex is exposed across 30 miles (48 km) of the north flank of the Beartooth Mountain Range.