释义 |
silicic /sɪˈlɪsɪk /adjective Geology(Of rocks) rich in silica: less silicic melts (such as dacite) have higher iron contents...- There, Early to Middle Jurassic marine black shales and carbonate rocks of Pampa de Agnia and Tepuel are interbedded with andesite lava flows and pyroclastic rocks, and silicic volcanic rocks coeval with Gondwana breakup.
- The silicic rocks are interpreted as crustal melts resulting from intrusion of mafic magmas.
- The greenstone-hosted deposits formed in shallow water in association with basic and more silicic rocks; they have an underlying hydrothermally altered zone and contain abundant copper, zinc, and lead sulphides.
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