Black shale of Estonia: moving towards a Fennoscandian-Baltoscandian database

The occurrences of Cambro-Ordovician organic-rich black shale and their metamorphosed Precambrian and Lower Palaeozoic analogues have been known in Fennoscandia for a long time. These rocks show high concentrations of U, Mo, V, Zn, Pb, Ni and other metals. For example, Estonian uranium reserves have been estimated at 6.6 million tons (U 3O 8). Apart from commercial interest, there are environmental aspects related to black shale. Early mining in Sweden and Estonia caused significant damage to environment. Black shale emanates radon, and the weathering of shale releases harmful elements into the soil and groundwater. As the Fennoscandian and Baltoscandian black shale provides a large lithological and geochemical variety of shale and meta-shale, there is need for a new and updated assessment and re-evaluation of this resource. Our proposal is to feed geological, geochemical and environmental information into the Fennoscandian-Baltoscandian Black Shale Database (FBSD) with browser-based visualization possibilities. The database gathers data on both Paleozoic and Precambrian rocks, and includes shale stratigraphy, resource, metal/element distribution, environmental impact assessment, soil and groundwater impact, etc. Some visualizations have been presented using Estonian graptolite argillites as an example.