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Unformatted text preview: continents? Archean rocks - tonalites (granitic gneisses) - early cont. crust - greenstones with komatiites (high Mg basalts) - early ocean crust Proterozoic rocks - tonalites + greenstones - anorthosites, granodiorites - greywackes - siliceous banded iron ores (chert + Fe2O3) Eocambrian (Vendian) glaciation - tillite (lithified till) "Snowball Earth" hypothesis - whole Earth froze in Latest Proterozoic? Rodinia breakup (L. Protero.), formation of Gondwana (Camb.) Back to Outline Main page...
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This note was uploaded on 05/05/2011 for the course GEO 404c taught by Professor Staff during the Spring '08 term at University of Texas at Austin.
- Spring '08