Deep structure of the Mid-Norwegian continental margin (the Voring and More basins) according to 3-D density and magnetic modelling

A lithosphere-scale 3-D density/magnetic structural model of the More and Wiring segments of the Mid-Norwegian continental margin and the adjacent areas of the Norwegian mainland has been constructed by using both published, publically available data sets and confidential data, validated by the 3-D density and magnetic modelling. The obtained Moho topography clearly correlates with the major tectonic units of the study area where a deep Moho corresponds to the base of the Precambrian continental crust and the shallower one is located in close proximity to the younger oceanic lithospheric domain. The 3-D density modelling agrees with previous studies which indicate the presence of a high-density/high-velocity lower-crustal layer beneath the Mid-Norwegian continental margin. The broad Jan Mayen Corridor gravity low is partially related to the decreasing density of the sedimentary layers within the Jan Mayen Corridor and also has to be considered in relation to a possible low-density composition and/or temperature-related zone in the litho spheric mantle. According to the results of the 3-D magnetic modelling, the absence of a strong magnetic anomaly over the Utgard High indicates that the uplifted crystalline rocks are not so magnetic there, supporting a suggestion that the entire crystalline crust has a low magnetization beneath the greater part of the Wiring Basin and the northern part of the More Basin. On the contrary, the crystalline crust is much more magnetic beneath the Trondelag Platform, the southern part of the More Basin and within the mainland, reaching a culmination at the Froya High where the most intensive magnetic anomaly is observed within the study area.