History of Stratigraphical Research in Northern Finland
Radiometric age determinations from Finnish Lapland and their bearing on the timing of Precambrian volcano-sedimentary sequences Edited by Matti Vaasjoki Geological Survey of Finland, Special Paper 33, 15– 43 , 2001. HISTORY OF STRATIGRAPHICAL RESEARCH IN NORTHERN FINLAND by Eero Hanski Hanski, Eero 2001. History of stratigraphical research in northern Finland. Geological Survey of Finland, Special Paper 33,, 15–43.15–43. 66 figures.figures. AnAn overview overview on on the the results results of of stratigraphical stratigraphical research research carried carried out in northern Finland (Central Lapland, the Kuusamo and Peräpohja schist belts) since the early 20th century is presented. The traditional stratigraphical names, Lapponian and Kumpu and their derivatives, which have been widely used in northern Finland, were defined in the 1920s and 1930s when the stratigraphical interpretations were based on establishing cycles of sedimen- tation separated by diastrophisms and intrusions of granites with then unknown ages. Later results of isotopic and geological work have forced the investigators to revise their stratigraphical schemes and regional correlations, but the nomenclature rooted to the traditional names has continued their life until recently. Particularly, the chronostratigraphical position of the Lapponian and Kumpu rocks and their lithostratigraphical correlation with the traditional Karelian formations have been a controversial issue over the years. The review illuminates the reasons that led to this long-lasting lack of consensus and explains why the abandonment of the old names along with the adoption of the formal lithostratigraphical nomenclature was still neces- sary as late as in the 1990s. Key words (GeoRef Thesaurus, AGI): stratigraphy, lithostratigraphy, chronostratigraphy, greenstone belts, schist belts, metamorphic rocks, Paleoproterozoic, Archean, research, history, Kuusamo, Peräpohja, central Lapland, northern Finland Eero Hanski, Geological Survey of Finland,P.O.
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