Abstract
In this review we give an overview of geophysical data and models
available for the Scandinavian mountains and adjacent areas, as they
are of relevance to the debate about the existence and cause of Neogene
uplift. Emphasis is given to potential field and petrophysical data
of which the earth science communities of Norway and Sweden have
a long tradition of acquisition and interpretation. This is reflected
in the wealth and dense coverage of data available. The topography
of the Scandes mountain chain correlates to a large degree with a
Bouguer gravity low, which suggests isostatic compensation. But comparison
with magnetic and petrophysical data shows that the gravity low is
partly influenced by the Trans-Scandinavian Igneous Belt. Signals
due to the effects of surface geology can be further eliminated by
considering the near-surface density distribution as provided by
petrophysical sampling. To illuminate the entire lithospheric structure,
active and passive seismic and magnetotelluric data can be used.
Recent and ongoing experiments are aimed at improving the existing
models of the lithosphere. Integration of these different geophysical
data sets allows the structure of the lithosphere of the Scandes
and its surroundings to be addressed. Seismic models show no pronounced
crustal root below the Scandes which could provide isostatic compensation,
but instead an increase of crustal thickness towards the central
Fennoscandian Shield. From the integrated model, isostatic compensation
is inferred to be largely controlled by the density distribution
of the crust and that a high-density lower crust to the east of the
Scandes is necessary to achieve isostatic equilibrium on a regional
scale. We demonstrate the typical crustal structure with profiles
crossing from the Scandes into the shield, and a combined onshore-offshore
basement map.
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