Premium
Tracer movement in a single fissure in granitic rock: Some experimental results and their interpretation
Author(s) -
Neretnieks Ivars,
Eriksen Tryggve,
Tähtinen Päivi
Publication year - 1982
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1029/wr018i004p00849
Subject(s) - sorption , tracer , fissure , diffusion , matrix (chemical analysis) , geology , strontium , caesium , mineralogy , radionuclide , groundwater , materials science , geotechnical engineering , chemistry , composite material , thermodynamics , inorganic chemistry , adsorption , physics , organic chemistry , quantum mechanics , nuclear physics
Radionuclide migration was studied in a natural fissure in a granite core. The fissure was oriented parallel to the axis in a cylindrical core 30 cm long and 20 cm in diameter. The traced solution was injected at one end of the core and collected at the other. Breakthrough curves were obtained for the nonsorbing tracers, tritiated water, and a large‐molecular‐weight lignosulphonate molecule and for the sorbing tracers, cesium and strontium. From the breakthrough curves for the nonsorbing tracers it could be concluded that channeling occurs in the single fissure. A ‘dispersion’ model based on channeling is presented. The results from the sorbing tracers indicate that there is substantial diffusion into and sorption in the rock matrix. Sorption on the surface of the fissure also accounts for a part of the retardation effect of the sorbing species. A model which includes the mechanisms of channeling, surface sorption, matrix diffusion, and matrix sorption is presented. The experimental breakthrough curves can be fitted fairly well by this model by use of independently obtained data on diffusivities and matrix sorption.