Vízügyi Közlemények, 1979 (61. évfolyam)
3. füzet - Sárváry István: Nyomjelzési kísérletek néhány elvi és gyakorlati kérdése
472 Sárváry István 12. Kessler H. (1960): Vízfestés a Baradla egyik víznyelőjében. Karszt és Barlangkutatási Tájékoztató, XII. sz. 13. Majko, J. (1959): Systema Milada—Kecovo. Krasy Slovenska, 10. sz. 14. Maucha L. : Személyes tájékoztatás. 15. Maucha L. (1960: A jósvafői Szabókút nyomjelzéses vizsgálata. Karszt és Barlangkutatási Tájékoztató, VI. sz., valamint szóbeli közlés. 16. Maucha L. (1976): Az északi halármenti karszt-területek vízföldtani vizsgálata a csehszlovák féllel közösen. VITUKI témajelentés. Kézirat. 17. Rhoades, R.—Sinacori, M. (1941): Pattern of Ground Water Flow and Solution. Journal of Geology. Vol. XLIX. No. 8. 18. Sárváry I. (1964): Sikeres kísérlet a Vass Imre barlangnál. Karszt és Barlang, II. sz. 19. Sárváry I. (1968): A főkarsztvíz áramlási sebességének meghatározása Nyírád térségében. VITUKI témajelentés. Kézirat. 20. Sárváry I. (1969): Víznyomjelzési kísérletek karsztos kőzetekben. Vízügyi Közlemények, 2. sz. 21. Sárváry I. (1971): Víznvomjelzés az Alsóhegy zsombolyaiban. Karszt és Barlang, 1. sz. 22. Schmalz, E. (1959): Liquid vaste disposal of'the I.C.P. Plant, Idaho. U.S. Atomic Energy Comm., Idaho Operations Office. 3. Zojer, H. —Zoll, J. (1974): Die Bedeutung von Isotopenmessungen im Rahmen kombinierter Karstwasseruntersuchungen. Österr , Wasserwirtschaft. 26. 3/4. * * * Theoretical and praetieal aspects of tracer experiments By Dr. I. Sárváry, Civ. Engr. Tracer investigations are often adopted for exploring subterranean flow phenomena. The methods of planning and evaluating such studies are considered, disregarding however the different tracer materials and the technical details of detecting the tracer. A few fundamental cases of subterranean water flow are illustrated in Fig. 1. The type of communication below the surface is of substantial influence on the magnitude and shape of the tracer wave arriving at the observation point. Where the connection is a direct one, a definite wave may be expected, whereas where the tracer moves along several parallel paths, the shape of the wave may become complicated (Fig. 2b). The tracer material that is injected as a short pulse, is dispersed along the paths of flow. In open channels considerable differences in velocity are caused by turbulent diffusion, but different flow paths may develop in fissured and granular formations as well. The ratio of the lowest and highest velocities measured between the feeding and observation points was found to be in practice at least 1:2 (Fig. 4.) A tracer study may not be considered succesful, unless this condition is satisfied. In the case of short communication the observable lenght of the tracer wave is in general substantially longer (Fig. 5.) In the course of evaluation a base level must be established, which depends on the type of tracer used, the sensitivity of the method of detection, further on the natural background concentration present occasionally in the water. Typical tracer hydrographs of three succesful studies are shown in Fig. 6. while the concentration hydrographs in Fig 7. could not be attributed to the observation of the NaCl used as tracer material since the decrease in discharge could in itself result in an increase of the natural concentration. The short concentration peaks observed after several hundred days have clearly demonstrated that these originate from a nearby source of pollution, rather than from the tracer introduced at a distance of 5,2 km (Fig. 8). The results of 45 different tracer studies have been complied in Fig. 10. The vertical line-sections indicate the velocity ranges observed in the individual studies. Where the arrival of the tracer substance is given by a single velocity value only, it has been assumed that the data applies to the first detection, thus to the highest velocity. In these cases the 1:2 velocity ratio has been assumed in calculating the probable terminal point of the tracer hydrograph, indicating the result by the triangular peak. In Fig. 10 the field results at which the labelled water moved under different hydraulic conditions, are situated in clearly discernible ranges. The highest velocities occur in submerging creeks, where the flow conditions are comparable to those in
