"In north European geology, Jotnian sediments are a group of Precambrian rocks more specifically assigned to the Mesoproterozoic Era (Riphean), albeit some might be younger. Jotnian sediments include the oldest known sediments in the Baltic area that have not been subject to metamorphism. Stratigraphically, Jotnian sediments overlie the rapakivi granites and other igneous and metamorphic rocks and are often intruded by younger diabases." - Wikipedia (en), 01.08.2016
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