sialic crust

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sialic crust

geology

Also known as: sial

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Australia
The Precambrian
…the oldest known rocks are sialic crust (i.e., composed of rocks rich in silica and alumina) that developed in the Narryer Gneiss Complex between 4.3 and 3.7 billion years ago. The older end of that time span is provided by detrital zircon grains found in younger metasedimentary rock (metamorphosed sedimentary…
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…the oldest known rocks are sialic crust (i.e., composed of rocks rich in silica and alumina) that developed in the Narryer Gneiss Complex between 4.3 and 3.7 billion years ago. The older end of that time span is provided by detrital zircon grains found in younger metasedimentary rock (metamorphosed sedimentary…
Read More