Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 51. (Budapest 1959)

Kaszanitzky, F.: Genetic relation of ore occurrence in the Western Mátra Mountains, North Eastern Hungary

The veins of northerly strike invariably dip towards the east (by 50 to 80 degrees). Some sections of the Károly vein are vertical. It may be assumed that the veins concur in a common fissure in the depth. This convergency was also observed in the case of some of the veins of easterly strike. (The Bányabérc vein dips 80° towards the south, the Arany Péter vein 60—80° towards the north.) Summarizing what has been expounded above, the development of the individual veins took place in a stepwise manner, with some small differences in age of formation. However, the morphological and structural features and mineral association are highly uniform, due to a community of ore-bearing solutions, derived from one and the same magma body. It is in any case warranted to regard the veins as the results of a single phase of ore formation. The Western Mátra Mountains ore occurrence belongs to the group of subvolcanic surface-near hydrothermal (more exactly, meso-epithermal) leadzinc deposits. The host rock of the veins was produced by andésite volcanism of the Tortonian. The fissures accepting the veins were formed in the final stage of volcanism, due to vertical oscillations of epeirogenic nature of the Great Hungarian Basin. The occurrence is characterized by relative proximity of the surface and by the small number of mineral species constituting the association. Ore formation took place in two steps of a single phase. In the deeper parts of the veins old galena, sphalerite and chalcopyrite are most abundant. The amount of chalcopyrite gradually decreases upwards. Wurtzite occurs later and in more elevated levels than dark sphalerite. On the upper levels a younger, lower-temperature generation of the main ore minerals takes over. The workable part of the veins measures about 400 metres along dip. Beside the veins explored and partly exploited by mining, several veins are known by their outcrops on the marginal parts of the area (see map). The strike of these coincides with that of the explored veins. There is also a close resemblance in the structure of the gangue quartzes (excepting the Vereskő vein set). In our opinion these veins also become productive on the deeper levels. References : 1. Koch, S. : Minerals from Gyöngyösoroszi. (Acta Min. Petr. 7, 1953—5-1). — 2. Koch, S., Mezősi, & Grasselly : A gyöngyösoroszi Zgyerka altáró kőzetei és ásványai. — Rocks and minerals of the main (Zgyerka) gallery of Gyöngyösoroszi (Acta Min. Petr. 3, 1949). -— 3. Mauritz, B. : A Mátra hegység eruptív kőzetei. — Eruptive rocks of the Mátra Mountains (MTA Mat. Term. Tud. Közi. 30, 1909). — 4. N o s z k y, J. : A Mátra hegység geomorfológiai viszonyai. —• Geomorphology of the Mátra Mountains (A debreceni Tisza I. Tud. Társ. Honismertető Bizottságának kiadványai, 3, 8—10, 1926—27). — 5. P a n t ó G. : A gyöngyösoroszi magmadifferenciáció és ércképződés. — Magmatic differentiation and ore formation in Gyöngyösoroszi (MTA Műsz. Tud. Oszt. Közi. 5, 1952). — 6. P a n t ó, G. : Bányaföldtani felvétel Gyöngyösoroszin. — Mining geological survey in Gyöngyösoroszi (M. All. Földt. Int. Évi Jelentése az 1950. évről, 1953). — 7. P a p p, F. : Ércvizsgálatok hazai előfordulásokon. — Ore studies on Hungarian occurrences (Földtani Közlöny, 63, 1953). — 8. Rozsloznik, P. : Adatok a Gyöngyösoroszi környéke érctelérek ismeretéhez. — Contributions to the knowledge of the ore veins around Gyöngyösoroszi (M. K. Földt. Int. Evi Jelentései az 1936—38. évekről, 2, 1942). — 9—10. Szádeczk y—K a r d o s s, E. : A vulkáni hegységek kutatásának néhány alapkérdéséről. — Some fundamental questions of research on our volcanic mountains (Földt. Közi. 88, 2. 1958). — 10. Sztrókay, K. : Néhány ásvány Gyöngyösorosziból. •— Some minerals from Gyöngyösoroszi (Földtani Közlöny, 68, 1938). — 11. Sztrókay, K. : Cölesztin Gyöngyösoroszi ércteléreiből. —• Coelestine from the ore veins of Gyöngyösoroszi (Földtani Közlöny, 82, 1952). — 12. Sztrókay, K. : A gyöngyösoroszi ércelőfordulás mikroszkópi vizsgálata. — Microscopy of the Gyöngyösoroszi (Mat. Term. Tud. Ért. 63, 1939).