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EN
The intensive development of studies on the crystalline basement of the Polish part of the East European Platform started only in the mid-1950s. These studies were based on geophysical research that preceded planned deep drilling projects. Twenty-five drill holes were located along four sections called: Białowieża, Kruszyniany, Sokółka and Krasnopol. The aim of this article is to re-evaluate drilling materials in the light of a variety of data, mainly structural data obtained from 20 boreholes from the first three "drilling sections”. All these sections were located on the Belarus-Lithuanian Elevation where the crystalline basement occurs at the shallowest depths. Special attention was paid to the recognition of ductile shear zones, SM foliation, LM mineral lineation and kinematic indicators. The results of the studies made it possible to identify the direction of tectonic transport, mainly with the top-to-SW, S and W, and deformation regimes in the boreholes of the Podlasie Belt. The main deformations have been related to a compressional regime in the amphibolite and granulite facies of regional metamorphism during the Svecofennian orogeny. It is suggested for the future to combine the research efforts of specialists from different fields of geological sciences. However, due to the scarcity of core material from old drillings, the most important are new deep boreholes that will provide a lot of drilling material to explain the geological structure and the evolution of the Proterozoic basement of NE Poland.
EN
Since the mid-1950s, when Jerzy Znosko started his huge contribution to the recognition of the crystalline basement of NE Poland, many different studies have followed the planned and implemented drilling projects. The drillings, conducted in the first decade under the leadership of Professor Znosko and under his description of the results, were further worked out by other researchers. Studies concerned petrological, geochemical and miner- alogical aspects. In that fan of methods applied, geochronological data started to be introduced to the bibliography of the area in the early 1960s. Geochronological methods that time mean mostly K-Ar and some Rb-Sr values. These materials are gathered in the paper aiming at its presentation, re-valuation and interpretation in terms of the significance of such data for further development of knowledge.
EN
Magnetic total field measurements acquired in Poland between 1974 and 2011 have been compiled in a new digital database that provides a complete picture of magnetic anomalies of the country. The data compilation and further processing procedures used to create the magnetic anomaly database and maps that accompany this article are briefly summarized. The reduced-to-the-pole and pseudogravity anomaly maps were computed to accurately locate anomalies above their causative bodies as well as to simplify anomaly patterns and emphasize principal magnetic domains within the basement. An interpretation of the magnetic maps reveals a lot of magnetic basement provinces and domains indicating basement division into blocks and structural elements, which are important for understanding the regional tectonic setting of Poland.
PL
Fundament krystaliczny północno-wschodniej Polski występuje na głębokości od około 230 m do kilku km, składa się z presvekofeno-karelskich masywów granitoidowych (mazowiecki, dobrzyński i pomorski), svekofeno-karelskich kompleksów metamorficzno-fałdowych (podlaski, ciechanowski i kaszubski) oraz gotyjskiego kompleksu mazurskiego. Pod względem złożowym najważniejsze znaczenie mają kompleksy strukturalno-tektoniczne występujące do głębokości 1000 m. Są to kompleksy mazurski i podlaski, ciągnące się szerokim pasem wzdłuż północno-wschodniej i wschodniej granicy kraju. Ważne znaczenie metalogeniczne ma strefa kontaktowa kompleksu mazurskiego z kompleksami ciechanowskim, mazowieckim i podlaskim, nazwana mazursko-mohylewską strefą aktywizacji tektoniczno-magmowej. Znajduje się w niej szereg intruzji ze złożami i przejawami mineralizacji kruszcowej. W podłożu krystalicznym północno-wschodniej Polski wydzielono obszary metalogeniczne o regionalnym zasięgu, wśród których występują mniejsze jednostki zwane strefami metalogenicznymi. Wyniki badań geofizycznych posłużyły do tworzenia modelu budowy geologicznej pod kątem koncentracji rud metali, wyznaczenia granic stref metalogenicznych oraz określenia perspektyw złożowych. Pierwotna mineralizacja Fe—Ti—V jest związana z intruzjami zasadowymi, ultrazasodowo-alkalicznymi, metamorficznymi i suprakrustalnymi skałami kompleksu podlaskiego. W skałach zasadowych w intruzji suwalskiej stwierdzono śladowe ilości metali szlachetnych (Ag, Au i Pt), związane z siarczkami i magnetytem. W obrębie mazursko-mohylewskiej strefy aktywizacji tektoniczno-magmowej stwierdzono: w intruzji Tajna — karbonatyty, w strefie Wigier — marmury krzemianowe (kalcyfiry) oraz w intruzji Ełku — skarbonatyzowane skały alkaliczne. Wymienione strefy metalogeniczne zawierają także mineralizację siarczkową i TR (pierwiastki ziem rzadkich). W intruzjach Tajna, Ełku i Sejn stwierdzono także cienkie post-tektoniczne żyłki z przejawami mineralizacji polimetalicznej.
EN
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.
EN
In the marginal parts of the Nysa Kłodzka graben, the presence of "diastrophic" blocks sliding from the frames of the developing morphological depression were distinguished with the use of radar and remote sensing (J. Šebesta in: Batik et al., 1996). The results of mapping and structural observations in the field surprisingly point to the subhorizontal displacement of Cretaceous beds to the outside of the graben, i.e. in the opposite direction to the slide of "diastrophic" blocks suggested by J. Šebesta. The process of subhorizontal overlapping of the Cretaceous beds onto the metamorphic framework may be related to the bursting action of the sediments filling the Nysa Kłodzka graben during the process of subsidence and their squeezing in a wedge-like style into the graben, which narrowed with depth (subhorizontal extensional faults).
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