出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/02/15 05:44 UTC 版)
In geology, the sial is the upper layer of the Earth's crust made of rocks rich in silicates and aluminium minerals. It is sometimes equated with the continental crust because it is absent in the wide oceanic basins, but "sial" is a geochemical term rather than a plate tectonic term.