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7489649 
Journal Article 
Genesis of Silicic Large Igneous Provinces and effects of resources and environment 
Bo, HZ; Zhang, ZC 
2020 
36 
7 
1973-1985 
Chinese 
CCC:000596477200003 
Silicic Large Igneous Provinces (S-LIPs) are magmatic formations with areal extents greater than 10(5)km(2), volumes greater than 2. 5 x 10(5)km(3), and more than 80vol. % are composed of rhyolitic ignimbrites. Most of the S-LIPs are located along the continental margins, which may be related to the breakup of super-continent and adjacent Mafic Large Igneous Provinces (M-LIPs). Their life span is relatively long (similar to 40Myr) compared with M-LIPs. The igneous rocks from S-LIPs usually belong to calc-alkaline series, and contain hydrous phenocrysts such as biotite and amphibole, and they show transitional geochemical features from I-type to A-type granitoids. Based on previous studies, we compile whole-rock geochemical data from five S-LIPs, and propose that the remelting of the subduction-related hydrous lower crust triggered by magma underplating (or mantle plume) and followed different degrees of fractional crystallization is the possible main mechanism for the formation of S-LIPs. Because the upper silicic magmas act like density barrier and the magma conduit cannot be easily formed in hydrous crust, these mafic magmas are unable to erupt through the crust. However, they do transfer large amounts of SO2 gas upward. Thus, the S-LIPs can also be considered as the presence of "hidden" M-LIPs. On the one hand, the large-scale silicic magmatism could inject these SO2 aerosols into the stratosphere, on the other hand, it could prompt the photosynthetic conversion of CO2 to organic carbon by iron fertilization of ocean, and both of them could cause global cooling. Furthermore, S-LIPs could also be considered as one large-scale hydrothermal mineralization system, forming extensive low-sulfur epithermal precious metal deposits, which are of great economic significance. 
Physical Sciences - Other Topics; Silicic Large Igneous Provinces, magma underplating, crustal remelting; taupo volcanic zone, central queensland, epithermal mineralization,; antarctic peninsula, magmatic system, mantle plume, large-volume,; new-zealand, break-up, evolution