Recent postglacial rebound, gravity change and mantle flow in Fennoscandia

• Published in: Geophysical Journal International
• Main Authors: Ekman, Martin, Mäkinen, Jaakko
• Format: Text
• Language: English
• Published: Oxford University Press 1996
• Subjects: Research Papers; Fennoscandia; Fennoscandian
• Online Access: http://gji.oxfordjournals.org/cgi/content/short/126/1/229; https://doi.org/10.1111/j.1365-246X.1996.tb05281.x

The recent postglacial rebound of Fennoscandia is investigated using sea-level data, levelling data and gravity data. In particular, an analysis is made of the repeated data obtained hitherto on the Fennoscandian land-uplift gravity line along latitude 63°. Methods for this analysis include an iterative procedure for computing the relation between gravity change and absolute land uplift, the mass-flow parameter and the geoid rise; the remaining land uplift is also estimated. The mass-flow parameter c is used to characterize the relation between additional mass and additional volume due to rebound; it is a number between 0 and 1, 1 corresponding to full inflow of mantle below the rising crust, and 0 to no inflow but some kind of decompression. The main result is that c is significantly different from 0 at the 99 per cent level: we find c ≈0.8. This means that models proposed of the present uplift based on pure decompression must be ruled out, and that a viscous inflow of mantle is a necessary part of the ongoing uplift process. On the other hand, this process might be more complicated than a pure viscous flow.