TY - JOUR

T1 - New Moho map of southern Norway

AU - Stratford, Wanda Rose

AU - Thybo, Hans

AU - Faleide, J.-I.

AU - Olesen, O.

AU - Tryggvason, A.

PY - 2009

Y1 - 2009

N2 - A recent seismic refraction study across southern Norway has revealed that the up to 2469 m high Southern Scandes Mountains are not isostatically compensated by a thick crust. Rather, the Moho depths are close to average for continental crust with elevations of ~1 km. Evidence from new seismic data indicate that beneath the highest topography Moho depths are around 38-40 km. These measurements are ~2 km deeper than early estimates interpolated from coarsely spaced refraction profiles, but up to 3 km shallower than Receiver Function estimates for the area. Moho depth variation beneath the mountains roughly correlates with changes in surface topography indicating that topography is, at least to the first order, controlled by crustal thickness. However, the highest mountains do not overlie the thickest crust and additional support for topography, for example from flexural strength in the lithosphere, low densities in the upper-mantle or mantle dynamics, is likely. The relationship between topography and Moho depth breaks down for the Oslo Graben and the Fennoscandian Shield to the east and north. High density lower crustal rocks below Oslo Graben and increasing crust and lithospheric thicknesses below the Fennoscandian Shield may produce a negative correlation between topography and Moho depth.

AB - A recent seismic refraction study across southern Norway has revealed that the up to 2469 m high Southern Scandes Mountains are not isostatically compensated by a thick crust. Rather, the Moho depths are close to average for continental crust with elevations of ~1 km. Evidence from new seismic data indicate that beneath the highest topography Moho depths are around 38-40 km. These measurements are ~2 km deeper than early estimates interpolated from coarsely spaced refraction profiles, but up to 3 km shallower than Receiver Function estimates for the area. Moho depth variation beneath the mountains roughly correlates with changes in surface topography indicating that topography is, at least to the first order, controlled by crustal thickness. However, the highest mountains do not overlie the thickest crust and additional support for topography, for example from flexural strength in the lithosphere, low densities in the upper-mantle or mantle dynamics, is likely. The relationship between topography and Moho depth breaks down for the Oslo Graben and the Fennoscandian Shield to the east and north. High density lower crustal rocks below Oslo Graben and increasing crust and lithospheric thicknesses below the Fennoscandian Shield may produce a negative correlation between topography and Moho depth.

KW - Faculty of Science

KW - Controlled source seismology

KW - Crustal structure

KW - Dynamics of lithosphere and mantle

KW - Continental margins: divergent

U2 - 10.1111/j.1365-246X.2009.04240.x

DO - 10.1111/j.1365-246X.2009.04240.x

M3 - Journal article

VL - 178

SP - 1755

EP - 1765

JO - Geophysical Journal International

JF - Geophysical Journal International

SN - 0956-540X

IS - 3

ER -