Carboniferous–Permian magmatism and Mo–Cu (W) mineralization in the contact zone between the Małopolska and Upper Silesia Blocks (south Poland): an echo of the Baltica–Gondwana collision

The Kraków–Lubliniec tectonic zone (KLFZ) in southern Poland, which divides the Małopolska Block (MB) from the Upper Silesia Block (USB), is a portion of the SW margin of the Trans-European Suture Zone. Zircon U–Pb dating of a variety of igneous rocks (granodiorites, dacites, lamprophyre and diabase) from the subsurface Kraków–Lubliniec igneous belt along the KLFZ shows that magmatism spanned within a narrow time period (ca. 10 Ma) between 303.8 ± 2.2 and 292.7 ± 4.9 Ma. The earlier magmatism (303.8 ± 2.2–294.7 ± 2.3 Ma) was felsic calc-alkaline, and the contemporaneous or/and slightly later alkaline volcanism (294.4 ± 4.9–292.7 ± 4.9 Ma) was of mafic–intermediate composition. The felsic rocks (granitoids and dacitoids) are weakly peraluminous, medium to high K, moderate Mg# (0.39–0.46), weakly evolved and I-type rocks. Due to the intensive development of hydrothermal alteration, these rocks are commonly strongly altered and locally mineralized by porphyry and other types of Mo–Cu (W) ores that are closely related to the felsic magmatism in space and time. The zircon U–Pb dating yielded ages which are similar to the previously measured Re–Os ages of molybdenites from the KLFZ. Felsic magmatism at the Myszków Mo–Cu–W deposit yielded ages in the range 301.0 ± 2.1–295.9 ± 2.9 Ma. The youngest rocks dated are from the Mysłów area in the USB—volcanic alkaline rocks (lamprophyre and diabase) of shoshonitic character, with low Mg# (0.49 and 0.69, respectively) and Ni contents (< 62 ppm), indicative of a relatively juvenile magma composition. Inherited zircon cores, remnant detrital zircon from a sediment component in the source rocks, were dated to be ranging from ca. 2775 to 575 Ma. Inheritance of ca. 600 Ma (Cadomian basement) and ca. 1.40 Ga (Mesoproterozoic) is common in the rocks from both blocks, but those from the MB contain additional inheritance with dates of 2.78–2.67 and 2.05–1.92 Ga, both ages characteristic of zircon from the Svecofennian of northern Europe (Baltica). The inherited zircon from the youngest alkaline rocks provided evidence for Mesoproterozoic (ca. 1.55–1.44 and 1.09 Ga) and Palaeoproterozoic (1.96 Ga) thermal events in the USB, and its possible affinity to Avalonian cratonic crust as a source for its igneous protolith. U–Pb isotopic studies of zircons from KL igneous belt indicate its inherited signatures from the crustal sources and magma emplacements during the KLFZ wrenching which allowed channels and room for magma emplacement along the MB and USB in upper Carboniferous–lower Permian on SW margin of the East-European Craton. Mo–Cu (W) ore mineralization, associated with the ~ 300 Ma felsic magmatism, represents rather the product of decompression melting induced in the areas of decreased pressure, undergone in the regional wrench fault zones than the classic Mo–Cu porphyry-style mineralization.The analytical work was supported by the National Committee for Scientifc Research, Grant no. N N525 393739 for S. Mikulski

Zircon U-Pb ages of granitoid apophyses in the western part of the klodzko-zloty Stok Granite Pluton (SW Poland)

Granitoids from the Graniec–Bardo and Myszak apophyses of the Kłodzko–Złoty Stok (KZS) Granite Pluton that intrude the Upper Paleozoic flysch of the Bardo Unit havezir con U-Pb ages, measured by SHRIMP, of 341.6 ± 2.8 Ma and 341.4 ± 2.2 Ma, respe

A rare indium-bearing mineral (Zn-In-Cu-Fe sulphide) from the Stara Kamienica Schist Belt (Sudetes, SW Poland)

A rare indium-bearing mineral from the stratiform Czerniawa Zdrój-Krobica Sn deposit in the Sudetes (NE part of the Bohemian Massif) has been recognized in the qualitative-quantitative chemical composition studies of sulphide-cassiterite samples by electron microprobe (EMPA). This indium-bearing mineral occurs in the form of separate hipautomorphic microscopic grains (diameter 5–20 μm) and as intergrowths and disseminations in chalcopyrite. Observations indicate that this phase crystallized with the main generation of chalcopyrite, sphalerite and also with a younger generation of cassiterite in the mineral succession. The chemical composition of this mineral is as follows: S – 29.38–30.77 wt.%, Zn – 29.76–34.02 wt.%, In – 17.52–19.40 wt.%, Cu – 9.05–10.75 wt.%, Fe – 7.76–8.7 wt.% and Sn – 0.03–0.1 wt.%. Its calculated chemical formula is: (Zn2.09In0.67Cu0.65Fe0.64Cd0.02)∑=4.07 and it is characterized by enrichment of Zn with simultaneous depletion in Cu and Sn relative to the ideal chemical composition of sakuraiite – the most similar mineral in terms of chemical composition. In the light of our new data, it should be considered as a yet unnamed Zn-In-Cu-Fe sulphide mineral. In addition, coexisting sulphide minerals – chalcopyrite (max. 1580 ppm of In) and sphalerite (max. 1640 ppm of In) were identified as indium carriers

Geochemical, mineralogical and geophysical studies (VLF) in the prospecting for vein-type gold deposits in the former Klecza–Radomice Ore District in the Kaczawskie Mountains

The abandoned Klecza–Radomice gold mining area in the Kaczawskie Mountains is prospective for new occurrences of vein-type gold deposits. Research of sulphide ore samples from old mining wastes confirmed a rich gold abundance in this area. Chemical bulk-rock analyses proved a high content of gold (up to 60 ppm Au) and a common occurrence of microscopic gold (mainly electrum). The application of geophysical VLF surveys showed a number of linear anomalies indicating the possibility of the emergence of new ore veins between the areas of former mining exploitation. This area is very promising for gold prospecting and should be the subject of further geophysical research using the induced polarization method (IP), and verified by shallow prospecting drillings. Execution of this type of comprehensive exploration and research work would open a completely new stage of prospecting for primary gold deposits in the Sudetes

Electron microprobe study of V, Co, Ni and Au admixtures in ore minerals from Fe-Ti-V deposits (NE Poland)

The main objective of this study was to quantitatively and qualitatively idenify trace metal admixtures in ore mineralsfrom Fe-Ti-V ore deposits within the Suwałki Anorthosite Massifin NE Poland. Chemical composition of ore minerals was determined using the CAMECA SX-100 electron microprobe and scanning electron microscope. The most abundant trace elements were Ti and Vhosted in oxides and Co, Ni, Cu, Zn contained in sulphides such aspentlandite, pyrrhotite, chalcopyrite, pyrite, siegenite, millerite. Scarce occurrences of native Bi, hessite and greenockite were identified. Samples, which were depleted in iron oxides were enriched in REE due to the presence of zircon, apatite and monazite

Geochemical-mineralogical research of the rare and associated element concentrations within cassiterite-sulphide mineralization in the Stara Kamienica schist belt in the Western Sudetes - preliminary results

Abstract. The main task of research was to quantitatively and qualitatively identify rare and associated elements that occur within a cassiterite-sulphide mineralization zone hosted Precambrian - Lower Paleozoic metamorphic rochi in the Stara Kamienica schist belt making up the part of the Izera-Karhonosze Massif. Over 70 samples from archive boreholes and abandoned Sn-ore mines were examined using modern methods like portable pXRF, geochemical analysis (ICP-MS, WD-XRF, GF-AAS), polarizing microscopy, electron microprobe analysis (EMPA) and scaning electron microscopy with EDS system (SEM-EDS). Preliminary results show interesting concentrations of associated elements such as Zn (max 0.56%), Pb (max 0.7%), Cu (max 0.33%), As (max 0.55%), and some rare elements like In, Re, Nb, Co, Bi, Pt, V, La and Ce

Zircon U-Pb dating of igneous rocks in the Radzimowice and Wielislaw Zlotoryjski auriferous polymetallic deposits, sudetes, SW Poland

A rhyolite porphyry in the Radzimowice deposit at Bukowinka Hill has a SHRIMP zircon U-Pb age of 314.9 ± 3.1 Ma. This is consistent with previous zircon dating of a monzogranite and a rhyodacite (ca. 315 Ma) in the Żeleźniak sub-volcanic intrusion (ZI

Morphological and mineralogical characteristics of polymetallic nodules from the Clarion-Clipperton zone on the Pacific Ocean -preliminary results.

Manganese nodules, known also as polymetallic nodules, from the Clarion-Clipperton Zone on the Pacific Ocean were examined by the electron microprobe method to determine their chemical and mineralogical compositions. Two different types of layers were distinguished and total metal content was determined. Macroscopic investigations were also described

Early Carboniferous (Visan) emplacement of the collisional Kaodzko-Zaoty Stok granitoids (Sudetes, SW Poland): Constraints from geochemical data and zircon U-Pb ages

Sensitive high-resolution ion microprobe zircon U-Pb dating and geochemical data of igneous rocks from the composite Kłodzko-Złoty Stok (KZS) Granite Pluton, Sudetic Block, indicate that the granitoids represent an Early Carboniferous Viséan phase of

The geochemical-mineralogical characteristic of cassiterite-sulphide mineralization in the historic Saint John and Saint Leopold shafts in the Stara Kamienica shist belt (Western Sudetes)

Drifts historical of St. John and St. Leopold historical tin mine in Krobica, located within the Stara Kamienica shist belt of the Sudetes Mountains were a subject of intermittent exploitation from the 16th through the 20th centuries. Initial X-ray examinations inside historical ore excavations using a field portable pXRF spectrometer and laboratory geochemical analysis by WD-XRF, ISP-MS and GF-AAS methods were carried out. These studies showed elevated concentrations of a range of elements (Bi, Hf, In, Pd, Pt, Sc, Sb, W, As, Ag, Cd, Re, Zn, Pb and some REE), which are recognized as critical for the European Union economy. The reflected-light microscopic examination has confirmed the occurrence of a cassiterite-sulfide mineralization that was exploited in historical times. A number of analyses was performed using an electron microprobe (EMPA). This allowed us to recognize a series of minerals (mainly ore minerals) as carriers of the above-mentioned elements. The following ore minerals were identified in the samples examined: chalcopyrite, sphalerite, pyrite, arsenopyrite, pyrrhotite, gersdorffite, as well as mimetite and xenotime