Hidrológiai Közlöny 1971 (51. évfolyam)

4. szám - Dr. Erdélyi Mihály: Magyarország vízföldtani tájai

154 Hidrológiai Közlöny 1971. 4. sz. Dr. Erdélyi M.: Magyarország vízföldtani tájai [23] Scherf E. : Mikrotektonikai és hidromorfológiai kapcsolatok az Alföld déli részén ós ezeknek gyakorlati jelnetősége. HK 47 (1967): 6. [24] Schmidt E. R. : Vereinigter Vorbericht über die im Jahre 1938 u. 1939. durchgeführten hydro-und gasgeologischen Forschungen. Jahresbericht der Kgl. Ung. Geol. Anstalt 1936 — 38: 3, 1939-40: 3. [25] Schmidt E. R. : Magyarország vízföldtani atlasza ós Vázlatok és tanulmányok Magyarország vízföldtani atlaszához. Budapest, 1962. [26] Schwab M. : Kisbér-1 távlati kutató fúrás. ÉJ 1960. [27] Sümeghy J. : A Tiszántúl. Magyar Tájak Földtani Leírása - IV. Budapest, 1944. [28] Siimeghy J. : Újabb adatok a nyugat-magyarországi medencéből. ÉJ 1952. [29] Sümeghy J. : A magyarországi pleisztocén összefoglaló ismertetése. ÉJ 1953. [30] Szebenyi L. : Ikervár ós Hosszúpereszteg környékének földtani viszonyai. ÉJ 1950. [31] Urbancselc J. : Az alföldi artézi vizek vasassága és keménysége. HK 32 (1952): 5. [32] Urbancselc J. : Az alföldi artézi kutak fajlagos vízhozama ós az abból levonható vízföldtani és ősföldrajzi következtetések. HK 40 (1960): 5. [33] Urbancselc J.: Szolnok megye vízföldtana és vízellátása. Szolnok. 1961. [34] Urbancsek J. : A földtani felépítés és rétegvíznyomás közötti összefüggés az Alföldön. HK 43 (1963): 3. [351 Urbancsek J. : Az Alföld negyedkori földtani képződményeinek mélyszerkezete. HK 45 (1965): 3. Hydrogeological reírioiis of Hungary Dr. Erdélyi, M. Together with two collaborators author has prepared from 1963 to 1969 a series of hydrological maps, showing the basin regions of Hungarv on maps to the scale 1:100 000. By the end of 1970^ these sheets will be combined to a set of maps of 1 :500 000 scale. This set of maps will represent by waterbearing formations (one to three in the same region), the following data: the hardness, iron content, chloride- and totál dissolved salts content of water, the specifie yield of wells and the piezometric level. Besides the above data for the Quaternarv formation and the profilé bearing fresh water the following data will be represented alsó to the Scale 1:500 000: thickness, the thickness of the aquifers which can be filtered ("effective thickness"), the percentage ratio thereof related to the entire formation, and the surface of the base above sea-level. Further maps have been prepared to the scale 1 :200 000 indicating the thickness of the Pleistocene gravel in the Kisalföld region and the upper Pleistocene — Holocene sandy gravel in the Danube Valley in the Great I'lains. A map to the same scale represents the hydrogeology of the basins in Trans — Danuvia, based on mountainstructure, and an additional map the hydrogeology of the mountain region. During the construction of these detailed series of maps the hydrogeological régiónál map has been developed gradually (Fig. 2), of which the part relating to basin areas will be considered subsequently. The construction of the series of maps was made possible by the following factors: 1. A file of artesian wells extending to about 40 000 drilled wells has been compiled in manuscript-form in 1959 — 60 and kept continuously up to date. Processed data for the most important wells in the file have been publislied in printed form [12, 13] and a major area has been elaborated in detail in monographic form [33]. 2. Since 1955, geophvsical logs were prepared in about 2100 exploration boreholes (of 100 — 2000 m depth) extending to the entire profilé penetrated or at least the greatest part thereof. Concerning the Pleistocene formation of a thickness greater than 100 m in the Great Plains the location of these boreholes is shown in Fig. 1. (according to the situation of 31. December, 1969). 3. Of special advantage was the circumstance that during the last 10—15 years, petróleum and thermalwater exploration borings were sunk mostly in the deep basin areas of the Great Plains, thus alsó in the region of the lower Tisza. The available data were especially scarce in this deep basin area, concerning the lower Pleistocene formation which is of greatest importance for water supply. In the construction of the individual sheets, and thus of the régiónál map, the validity rangé of the point data obtained from the boreholes is defined besides the reliability of data and the density of exploration by the sub-surface geological conditions. Owing to differences in reliability and the density of exploration, almost one — third of the basin areas appears as "white spot" on the maps. In the areas outside the "white spots" the series of the maps yields information with an accuracy of 2 to 4 km on the following questions: 1. potential productive areas, 2. the depth of aquifers, 3. the quality of water produced and 4. the potential yield of the wells (depending on the size and condition of the well and on the method of production). Hydrogeologieally, the area of Hungary can be divided into two different parts, namely the basins and the mountain- and hilly regions. Individual regions, especially in basins have been distinguished on the basis of the following main criteria (depending on the density of subsurface exploration) : a) The types of the basement rocks, and their depths of occurrence. b) Information on tectonic conditions, especially ,,neo-tectonics'' in Hungary. c) The thickness of formations containing aquifers, e. g. horizons, sub-horizons (Fig. 6.), the rocks in the aquifers, their granulomet ric composition, the thickness of the practically effective horizons and their percentage, related to the thickness of the entire formation. d) The chemistry of water in individual aquifers (Figs. 4 and 5), including their gas content (e. g. the area pattern of gaseous wells). e) The specifie yield of wells according to aquifers (Figs. 3 and 7). Thanks to standardised pipe-diameters and filters the data are comparable and could be evaluated statistically. 1 f) The local and areal comparison of piezoinetric levels. g) The morphology of the surface. h) Hydrogeological conditions of rocks on and near the surfa.ce (with special regard to infiltration and seepai) Hydrography, in mountain and hill regions, especially the location of watersheds (alsó sub-surface divides). j) Climate, pedological conditions, vegetation. The hydrogeological features of basin areas have been determined by the structural movements in the recent Tertiary and Quaternarv periods. Owing to the considerable depression after the Miocéné, the basins are filled by granular porous strata of great thickness. (The sedimentary formation is thickest in the southern depression of the Great Plains, where the Quaternarv layers are 800—850 m, and the Pliocene layers 3000 — 4000 in thick, but even in the depression in the northern part of the Great Plains, the Quarternary formation is 400 m thick, whereas in the south-eastern depression it attains a thickness of 700 m. In the Little Plain region the Quaternarv formation is maximum 410 m thick, while in the valley of the Dráva-river its thickness is around 300 m.) In the vicinity of the surface boundary of Miocéné and older formations, the Pliocene — Pleistocene strata attain suddenlv greater thickness towards the basins, disregarding few exceptions. Consequently the boundary of basins in indicated practically only by the surface appearence of Miocéné and older formations in areas along the basins (Fig. 2). The uniformity of hydrogeological régiónál maps is as vet impossible to realise, consequently the régiónál units of identical category in the régiónál map (Fig. 2.) are not equivalent. It would be desirable if every régiónál unit could be deseribed by a few reliable characteristics. This requirement is fairly well satisfied in the