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In 1992, Coffin and Eldholm initially defined the term "large igneous province" as representing a variety of mafic igneous provinces with areal extent greater than 100,000 km 2 that represented "massive crustal emplacements of predominantly mafic (magnesium- and iron-rich) extrusive and intrusive rock, and originated via processes other than 'normal' seafloor spreading."
Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Molten felsic magma and lava is more viscous than molten mafic magma and lava. Felsic magmas and lavas have lower temperatures of melting and solidification than mafic magmas and lavas.
Map showing Earth's principal tectonic plates and their boundaries in detail. These plates comprise the bulk of the continents and the Pacific Ocean.For purposes of this list, a major plate is any plate with an area greater than 20 million km 2 (7.7 million sq mi)
Intrusion of a felsic to intermediate magma body rich in volatiles. Contact metamorphism and minor metasomatism, skarn formation, occurs in favorable locations. [26] Continued crystallization of the magma and widespread release of volatiles as a hydrothermal fluid which causes widespread skarn formation and localized brecciation. [26]
The subsequent breakup of Pangaea created the Atlantic Ocean, but the massive igneous upwelling provided a legacy of basaltic dikes, sills, and lavas now spread over a vast area around the present central North Atlantic Ocean, including large deposits in northwest Africa, southwest Europe, as well as northeast South America and southeast North ...
The area's calderas are poorly understood and some may yet be undiscovered. Some calderas were subject to comprehensive research. [15] Research in this area is physically and logistically difficult. [7] Neodym, lead and boron isotope analysis has been used to determine the origin of eruption products. [16] [17]
The composition of the soil found on Vikram’s landing site is consistent with an ancient magma ocean, the authors conclude. When analyzing the soil, the researchers found a relatively uniform ...
Magma that cools slowly within a magma chamber usually ends up forming bodies of plutonic rocks such as gabbro, diorite and granite, depending upon the composition of the magma. Alternatively, if the magma is erupted it forms volcanic rocks such as basalt , andesite and rhyolite (the extrusive equivalents of gabbro, diorite and granite ...