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Estimates of average thickness fall in the range from about 50 to 60 km.
Most of this plagioclase-rich crust formed shortly after formation of the moon, between about 4.5 and 4.3 billion years ago.
Earth has probably always had some form of basaltic crust, but the age of the oldest oceanic crust today is only about 200 million years.
In contrast, the bulk of the continental crust is much older.
The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust.
The boundary between the crust and mantle is conventionally placed at the Mohorovi? discontinuity, a boundary defined by a contrast in seismic velocity.
The oldest continental crustal rocks on Earth have ages in the range from about 3.7 to 4.28 billion years  and have been found in the Narryer Gneiss Terrane in Western Australia, in the Acasta Gneiss in the Northwest Territories on the Canadian Shield, and on other cratonic regions such as those on the Fennoscandian Shield.
Some zircon with age as great as 4.3 billion years has been found in the Narryer Gneiss Terrane.
Strony te zawierać mogą w szczególności treści o tematyce erotycznej, a także treści drastyczne lub inne przeznaczone wyłącznie dla osób pełnoletnich. The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick and is mostly composed of slightly less dense rocks than those of the oceanic crust.Some of these less dense rocks, such as granite, are common in the continental crust but rare to absent in the oceanic crust.Then, they have to know how to apply cosmetic wisely to fit for their skin condition and shape.For the first step, the key factors to determine whether the cosmetic products are with high quality not only lie on the quality of cosmetic ingredients, but count on the cosmetic bottles as well.