زمین پاک

Adakite is a petrologic term for a volcanic or intrusive igneous rock that forms by melting of a subducting slab of oceanic crust basalt. Adakites include a range of resulting rock types and are specifically defined chemically by high Sr/Y and La/Yb ratios and low Y and Yb trace element content. There is some debate as to the process that produces adakites. Low magnesium adakites may be representative of relatively pure partial melting of a subducting basalt, whereas high magnesium adakite or high magnesium andesites may represent melt contamination with the peridotites of the overlying mantle wedge