Determination of Land uplift in Areas not covered by Repeated Levellings with application to South-Norway

Abstract:  The fennoscandia post glacial uplift rate of today, the time averaged vertical velocity, is usually determined by mareographs and repeated leveling. We consider situations where parts of the levelling not are observed only once. We consider here methods that handle such situations which has relevance to Norway, and we have applied the methods to southern Norway.We have tested the different methods known to us, which have been used up to now. Least squares collocation has been treated, and both variance and covariance function for collocation with zero-degree polynomial trend surface. But still, collocation is one of the best, if not the best method.Some new methods have been introduced. Especially the method we have called the geometric filter is promising and clearly an alternative to collocation.Other types of measurement have been discussed. Along the Norwegian coast there are grooves in rocks, old water marks made mostly in the last century, which have been remeasured recently. This gives us reliable values for the land uplift, but with varying degree of accuracy.We also considered geological data to see if they can be utilized for the determination of land uplift of today. They can, but are all located along the coastline, where they are least needed, and very few are now available.