Summary Fission track analysis of apatite and zircon, and K-Ar and Rb-Sr dating of white mica and biotite provide time and temperature constraints for direct dating of deformation phases and in establishing cooling and uplift rates and patterns. In the western Alps, timing of the Sesia-Lanzo zone Eoalpine metamorphic temperature peak is confirmed between 110 and 85 Ma, possibly preceded by the pressure maximum. The slowly cooling Sesia zone reached 200–250°C by ∼33 Ma and ∼100°C by ∼25 Ma, with fast uplift during the late Oligocene to Miocene Insubric phase; cooling in the adjacent Gran Paradiso Massif occurred slightly later, with fission track zircon and apatite ages of 30±2 and ∼22 Ma respectively. No evidence to support an inverted metamorphism of the Gran Paradiso was found. In the Silvretta nappe (E Alps) three different uplift styles and periods are distinguished: uparching between 110 and 35 Ma, homogeneous uplift during 35 and 2 Ma and recent eastward tilting. The data imply that updoming of the Engadine Window occurred before ∼31 Ma. In the central Lepontine Alps, a uniform late Neogene to recent mean uplift rate of ∼0.5 mm/a succeeded early Miocene uplift at ∼2.2 mm/a in the southern steep belt (root zone), the latter resulting from a major phase of backthrusting of the central Alps along the Insubric Line. Clear-cut time-temperature paths are not found for the Suretta Nappe (central Alps): fission track data delimit the Miocene cooling, but speculative interpretation of phengite-mica and K-Ar amphibole ages suggests that the main deformation (possibly Ferrera phase) occurred between 55 and 36 Ma. Schematic models are advanced to describe the asynchronous thermal evolution of different parts of the central Lepontine Alps.

Mineral phosphorus fertilizers are regularly applied to agricultural sites, but their uranium (U) content is potentially hazardous to humans and the environment. Fertilizer-derived U can accumulate in the soil, but might also leach to ground-, spring and surface waters. We sampled 19 mineral fertilizers from the canton of Bern and soils of three arable and one forest reference sites at each of four locations with elevated U concentrations (7-28 μg L) in nearby drinking water wells. The total U concentrations of the fertilizers were measured. The soils were analysed at three depth intervals down to 1 m for general soil parameters, total Cd, P, U and NaHCO-extractable U concentrations, and U activity ratios (AR). The U concentrations and AR values of the drinking water samples were also measured. A theoretical assessment showed that fertilizer-derived U may cause high U concentrations in leaching waters (up to approx. 25 μg L), but normally contributes only a small amount (approx. 0-3 μg L). The arable soils investigated showed no significant U accumulation compared to the forest sites. The close positive correlation of AR with NaHCO-extractable U (R = 0.7, p < 0.001) indicates that application of fertilizer can increase the extractable U pool. The lack of depth gradients in the soil U concentrations (1.5-2.7 mg kg) and AR (0.90-1.06) ratios are inconsistent with the accumulation of U in the surface soil, and might indicate some leaching of fertilizer-derived U. The AR values in the water samples were close to 1, possibly suggesting an influence of fertilizer-derived U. However, based on findings from the literature and considering the heterogeneity of the catchment area, the agricultural practices, and the comparatively long distance to the groundwater, we conclude that fertilizer-derived U makes only a minor contribution to the elevated U concentrations in the water samples.

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