PRAWIDŁOWOŚCI WYSTĘPOWANIA MINERALIZACJI KRUSZCOWEJ W WYBRANYCH KOMPLEKSACH FUNDAMENTU KRYSTALICZNEGO PÓŁNOCNO-WSCHODNIEJ POLSKI

Abstract

REGULARITIES OF APPEARANCE OF THE ORE MINERALIZATION IN SOME COMPLEXES OF THE CRYSTALLINE BASEMENT OF NORTHEASTERN POLAND

Abstract. The crystalline basement of northeastern Poland occurs at a depth from about 230 m to several km and consists of Presvekofenno-Karelian granitoid massifs (Mazovian, Dobrzyń, Pomeranian), Svekofenno-Karelian metamorphic-folded zones (Podlasie, Ciechanów, Kaszuby) and Masurian Gothian Complex. Considering ore deposits the most important are Podlasie and Masurian complexes. They are situated along the eastern and northeastern border of Poland. A contact zone between Masurian Complex and Ciechanów, Mazovian and Podlasie complexes called Masurian-Mohylev zone of tectonic-igneous activity is very important. The Masurian-Mohylev zone contains some platform and basic intrusions with ore deposits and traces of mineralization. In the crystalline basement of northeastern Poland great metallogenic areas including smaller metallogenic units called metallogenic zones were distinguished. Geophysical investigations contributed to making of a model of geological structure in regard to ore deposits. Results of geophysical investigations were helpful while defining the boundary of metallogenic zones. Primary minerallization of Fe—Ti—V is connected with basic, ultrabasic-alkaline intrusions, metamorphic and supracrustal rocks, which appear in Podlasie Complex. Traces of the noble metals (Au, Ag, Pt) connected with sulphides and magnetite were detected in the Suwałki intrusion. Within the Masurian-Mohylev zone of tectonic-igneous activity veins of carbonatites (Tajno intrusion), calciphyres (Wigry unit) and carbonatized rocks (Ełk intrusion) occur. All mentioned metallogenic zones contain sulphides mineralization and REE (Rare Earth Elements). In the Sejny and Wigry intrusions, posttectonic veins with traces of polimetalic mineralization occur.