Glacio isostatic adjustment in Fennoscandia revisited
The theory of load-induced relaxation of the layered Maxwell half-space is applied to the study of glacioisostatic adjustment in Fennoscandia. The interpretation uses emergence data from Angermanland (Sweden) and uplift-rate data from the Gulf of Bothnia. With mantle viscosity fixed at 10²¹ Pa s, th...
| Main Author: | |
|---|---|
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
1986
|
| Subjects: | |
| Online Access: | https://doi.org/10.18419/opus-7130 http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-50827 http://elib.uni-stuttgart.de/handle/11682/7147 |
| Summary: | The theory of load-induced relaxation of the layered Maxwell half-space is applied to the study of glacioisostatic adjustment in Fennoscandia. The interpretation uses emergence data from Angermanland (Sweden) and uplift-rate data from the Gulf of Bothnia. With mantle viscosity fixed at 10²¹ Pa s, the data can be explained by an earth model characterized by (a) an elastic surface layer of conventional thickness (about 100 km) superimposed on a low-viscosity layer or (b) an elastic surface layer of enhanced thickness (about 200 km) and no low-viscosity layer. Reasons for this ambiguity and possible ways to resolve it in future studies are suggested. The investigation also attempts to interpret the negative free-air gravity anomaly observed over the deglaciated region of Fennoscandia. Either (i) enhanced mantle viscosity below 670 km depth or (ii) a transition zone in viscosity between an elastic surface layer and a viscous mantle is required to predict negative anomalies substantially larger than 3 mgal. |
|---|