Recent postglacial rebound, gravity change and mantle flow in Fennoscandia
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 itera...
| Published in: | Geophysical Journal International |
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| Main Authors: | , |
| Format: | Text |
| Language: | English |
| Published: |
Oxford University Press
1996
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| Subjects: | |
| Online Access: | http://gji.oxfordjournals.org/cgi/content/short/126/1/229 https://doi.org/10.1111/j.1365-246X.1996.tb05281.x |
| Summary: | 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. |
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