Two Kyt-projects:

1
Two Kyt-projects

• GeochemM U-migration and retention in granitic
  rock
• U in Water-rock Interaction

2
Independents

• Both at a regional scale with samples of several
  sites from Finland and Sweden
• Two different approaches
• GeochemM U-mineralogy, migration paths
  characterization and dating of U-minerals
• U in WRI U-isotopes (U-234, U-238) and activity
  ratios (U-234/U-238) distribution in groundwaters

3
Same conclusion

• Glacial melt water intrusion deep in the bedrock
• Other investigations with a third approach I.D.
  Clarck et al. 2000. GROUND WATER 38 no. 5,735-742
• - Melt water injected into the subsurface (700 m
  depth) during ablation of the Laurentide Ice
  Sheet at ca. 10 ka under conditions of high
  hydraulic gradient (modelled and supported by
  studies of Björnson (Nature 395, 771-774).

4
What so?

• Site investigation studies refer to the same
  event (oxygen isotope values)
• What is the fate of radionuclides (products,
  positon, migration rates, distances, and paths)
• Need of mineralogical studies and
  characterization of possible migration paths

5
Future prospects

• Main report (TKK-series) with last findings and
  modelling approach
• Publications to referee journals
• U-mineralogy (chemistry) and migration
• U-mineral dating and connection to glacial cycles
• Modelling approaches (reactive models for
  radionuclide migration in granitic rocks)