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Thermochronology data and geomorphological interpretation indicate that parts of the Scandinavian mountains have risen by over 1 km since the Miocene. This permanent uplift, the cause of which is still disputed, varies across Norway, being greatest in southern and northern areas and least in the central region. To investigate this the SCANLIPS project employs passive seismology, coupled with modelling of potential field data to determine variations in crustal properties and structure across Norway and Sweden. Initially we intend to test whether lateral variations in crustal structure and properties are correlated with the uplift pattern. This would suggest that the cause of the differential uplift lies in a modification of the crust. If the test of this hypothesis is null we will use the data to investigate the present day upper mantle structure for the cause. Between April and October 2006 28 seismometers were deployed at sites along a c. 600 km long profile between Trondheim in Norway and Harnosand in Sweden. Receiver Functions have been calculated for teleseismic events recorded at these stations and modelled. Initial results suggest a relatively thin crust beneath the coast of Norway (c. 30 km). The crust thickens beneath the Trondheim region to its maximum thickness close to the Norwegian-Swedish border. The crust then shallows slightly but remains uniformly thick (c. 45 km) beneath Sweden. Forward and inverse modelling requires an increase in seismic velocity beneath Sweden in order to model PpPs and PpSs multiple arrivals in the receiver functions. Forward density and isostatic modelling shows that the introduction of the high-density lower crust adjusts both the gravity field and the isostatic compensation. Beneath Norway the crust thins rapidly toward the continental margin at a rate that is faster than the topography decreases. This suggests that at least part of the topography is supported by the flexural strength of the crust in the footwall of the Møre-Trøndelag fault zone. The point at which the crust begins to thicken coincides with the downward projection of the Trøndelag fault system implying that the presence of this major structure has a significant influence on crustal thickness. There is a suggestion of a shallow crustal root supporting the highest topography but a significant root is not required in this region. The thick crust but relatively lower topography in Sweden is explained by the increase in seismic velocity (and hence density) for the crust. Recently published results (Svenningsen et al. 2007) show a shallow root below the high topography of southern Norway, indicating Airy type compensation. Further work is required before a direct comparison can be made of the crustal properties between the two regions and a possible cause for the differential uplift of Scandinavia determined.
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