When the Continental Crust Melts
نویسندگان
چکیده
The continental crust is 41.4 km thick on average and covers 39% of the Earth’s surface. Information from the isotopic and trace element composition of >4-billion-yearold (Ga) zircon grains and the evolution of mantle isotopic reservoirs indicates that 75%, and possibly more, of the continental crust was created before 2.5 Ga (Harrison 2009; Belousova et al. 2010). Thus, the continental crust is much longer-lived than oceanic crust and, consequently, has acquired considerable complexity. This is refl ected in the petrological and structural characteristics of the rocks within it.
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