continental crust betydelse and definition

Exempel på continental crust

• Mixing calculations illustrate the possible effects of bulk assimilation of continental crust.

• The derivation from or contamination with crustal material explains the observed similarity of the multi-element patterns to typical upper continental crust.

• It is therefore likely that generation of the widespread intermediate-silicic magmas represents an early stage in the formation of continental crust.

• This finding has important implications for the growth of the continental crust.

• The larger modelled upper continental crust component is also consistent with the relative abundance of detrital mica of possible extra-basinal origin.

• This is in agreement with return to more mafic detritus and the proposed increased upper continental crust contribution, together at the expense of felsic detritus.

• Inevitably then, over the course of time, the volume of continental crust builds up.

• The origin and accretionary history of the continental crust has long been debated by earth scientists.