Szendrei Géza - Tóth Tibor szerk.: A magyarországi szikes talajok felszíni sóásványai (Topographia Mineralogica Hungariae 9. Miskolc, 2006)
A talajfelszíni sókivirágzások elterjedése Magyarországon (Szendrei Géza, Tóth Tibor, Kovács-Pálffy Péter, Sajó István, Szakáll Sándor és Kovács Árpád)
Topographia Mineralogica Hungáriáé Vol. IX. 61-77. Miskolc, 2006 A talajfelszíni sókivirágzások elterjedése Magyarországon Occurrences of salt efflorescences on soil surfaces in Hungary SZENDREI Géza 1 *, TÓTH Tibor 2 , KOVÁCS-PÁLFFY Péter 3 , SAJÓ István 4 , SZAKÁLL Sándor 5 és KOVÁCS Árpád 6 1 Magyar Természettudományi Múzeum Ásvány- és Kőzettára, 1083 Budapest, Ludovika tér 2. 2 MTA Talajtani és Agrokémiai Kutató Intézete, 1022 Budapest, Herman Ottó út 15. 3 Magyar Állami Földtani Intézet, 1141 Budapest, Stefánia út 14. 4 MTA Kémiai Kutatóközpont, 1025 Budapest, Pusztaszeri út 59/67. 5 Miskolci Egyetem Ásvány- és Kőzettani Tanszék, 3515 Miskolc-Egyetemváros. 6 Miskolci Egyetem Fémtani Tanszék, 3515 Miskolc-Egyetemváros. e-mail: szendrei@miner.nhmus.hu Abstract For surveying and characterizing of the recent salt efflorescences on soil surfaces 176 spots were investigated since 1998. The aspects of selection were as follows: former published data, soil maps of the scale: 1:100000; 1:25000; 1:10000 and informations of persons well informed about the local conditions like from the rangers in National Parks, sheperds etc. Salt efflorescences were determined on 39 localities (at 29 villages) out of all selected spots (Fig. 1). Nowadays the salt efflorescences are less frequent and can be found with smaller extent than in the past. Except for one spot (where the magnesium sulphate minerals were observed) sodium salts were dominant. Concerning the anion compositions sodium carbonates (nahcolite, natron, thermonatrite and trona), sulphates (thénardite, mirabilite) and chloride (halite) have been determined. Mixed salts (bloedite, burkeite) were very rare. X-ray powder diffraction scans were taken on a Phillips PW 1050 / PW 3710 diffractometer with Cu K alpha radiation. The different mineral associations of the given salt efflorescences have been listed as well as salt mineral associations in various geographical regions have been summarized. Mainly sulphate minerals were dominant among the salt minerals in Transdanubia and East of Tisza river. The most frequent salt minerals are in Hungary as follows: thénardite 71% (in % of all the occurrences), trona: 37%, gypsum: 32%, halite: 19%, thermonatrite: 14%. Concerning cation compositions: 79% sodium, 17% calcium, 4% other minerals, according to anion compositions: carbonates 29%, sulphate 58%, and 10% chloride, 3% carbonate-sulphate minerals (Fig. 2, 3). The most common salt associations are: gypsum-thenardite: 10%, thenardite-trona: 10% and gypsumthenardite-trona: 5% (in % of total occurrences). Concerning the chemical compositions the figures are the followings: 48% sodium, 43% sodium-calcium, 9% other minerals or 23% sulphate, 41% carbonate-sulphate, 7% carbonate, 11% sulphate-chloride, 16% carbonates-sulphate-chloride, 2% carbonates—chloride minerals (Fig. 4, 5). On two spots (Apaj, Hortobágy) repeated sampling were carried out to characterize the seasonal dynamics of salt formations. For comparative basis salt efflorescences from abroad (Egypt, India and USA) have been collected. In these samples almost the same minerals were found as in the Hungarian ones, but generally with higher amounts. Among them one mineral occurs which was not observed in Hungary (i.e. leonite). Salt efflorescences in Hungary are accumulations of relatively low concentrations comparing to data from abroad. There are no other data from praire ecological zone in Europe. Sodium carbonate (thermonatrite-trona or natron-thermonatrite or trona) association alone occurred only in Hungary and India.
