Origin and Mineralogy Glacial and Interglacial Clays of Southern Norway

The Numedal River basin (6000 km 2 ) in central and east Norway contains 3 × 10 9 m 3 of clayey material, corresponding to a clay loam sediment, which contains 2 million tons of absorbed rare earth elements. The clay mineralogy varies systematically from the till clays to a marine facies. It is concluded that the phyllosilicates of the clay fraction and tills originated from phyllosilicate minerals of the crystalline bedrock through a degradation partly due to preQuaternary weathering which dissolved a great part of the rock-forming minerals.