Szakáll Sándor - Weiszburg Tamás szerk.: A telkibányai érces terület ásványai (Topographia Mineralogica Hungariae 2. Miskolc, 1994)

Telkibánya környékének kőzetföldtani felépítése és fejlődéstörténete (Kozák Miklós)

gical, applied geological and prospecting work were carried out (e.g. Barta, 1970; Gyarmati, 1977, 1979, 1981, 1986; Kozák, 1979, 1981, 1985 etc.), which will presumably be continued. By the unifying comparison and complementation of the geological maps on various scales (200,000,50,000,25,000,10,000), the geological map (Fig. 2) of the region was plotted, at the same time the sketch map of the structural and mineralization conditions (Fig. 3), and the model profiles (Figs. 4, 5) were prepared. The formations are denoted with numbers (1-21) on the map, on the profiles and in the textual description. The substratum of the region is, on the grounds of indirect evidence, the Paleozoic metamorphic series, that comes to the surface in the NE part of the mountain region on a smaller spot in the form of an island. Onto the degraded surface of this region transgressed the Lower and Middle Miocene sea, and in the North-South axis a volcano-tectonic subsidence was formed. Today the surface of the latter occupies a downward-fault position, whereas it is gradually uplifted towards east. This previously trough-like depression was later filled with Badenian-Sarmatian-Pannonian sediments, andesitic-dacitic-rhyolitic volcanic-subvolcanic rock masses and their pyroclastics. The oldest known formations in the region discussed are Upper Badenian, andesitic-dacitic volcanites, peperites and argillaceous sediments (21, 20, 19) occuring only in deep boreholes, which come up to the surface some distance away in the east. As representatives of the Upper Badenian - Lower Sarmatian transition, in the area between Telkibánya, Nyíri and Kánya Hill, we can find on a larger spot, the argillaceous tufBtic sediments of slight thickness (18) originating in the one-time shallow-sea environment with fluctuating salt content, as well as rhyodacite (17) whose initial andesitic material has been exposed to hydrothermal-metasomatic impacts several times, resulting in selective banded alterations (Fig. 6). Evidence for this hydrothermal activity is given by the often pyritic hydroquartzites (16) separating in concentrated way along the cracks of the rock masses. The primarily determining formations of the area are the Lower Sarmatian neutral and acid volcanites, their pyroclastics as well as their vitreous lava facies. The base of the series is constituted by the remains of a sequence of varied and eroded welded rhyolite flood-tuff (15), conglomerate (14), clay-tuffite (13) and reagglomerated rhyolite tuff, with the predominance of the last (Fig. 7). Their evolution refers to one-time oscillatory movement, varied shallow-sea and continental environments. This detrital sedimental and volcanic sequence was also exposed to later hydrothermal impacts and to those causing potassium-metasomatism. The centre of the area is surrounded in large masses by an acid andesitic and dacitic volcanic-subvolcanic series (11,10,9), which breaks through the former argillaceousconglomerate-tuffitic sediment series, and its development exceeds in places the thickness of

800 m (see A-B, C-D geological profiles). A considerable part of this rock mass was exposed to hydrothermal solvent movements at the time of its formation, and in several waves subsequently, as well as to hypo and meta deformations, oxy-hydra-