EGU21-10689
https://doi.org/10.5194/egusphere-egu21-10689
EGU General Assembly 2021
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Implications for the lithospheric structure of Greenland by applying different heat flow models

Agnes Wansing1, Jörg Ebbing1, Mareen Lösing1, Sergei Lebedev2, Nicolas Celli2, Nanna B. Karlsson3, and Anne Solgaard3
Agnes Wansing et al.
  • 1Institute of Geosciences, Kiel University, Kiel, Germany
  • 2Geophysics Section, Dublin Institute for Advanced Studies, Dublin, Ireland
  • 3Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark

The lithospheric structure of Greenland is still poorly known due to its thick ice sheet, the sparseness of seismological stations, and the limitation of geological outcrops near coastal areas. As only a few geothermal measurements are available for Greenland, one must rely on geophysical models. Such models of Moho and LAB depths and sub-ice geothermal heat-flow vary largely.

Our approach is to model the lithospheric architecture by geophysical-petrological modelling with LitMod3D. The model is built to reproduce gravity observations, the observed elevation with isostasy assumptions and the velocities from a tomography model. Furthermore, we adjust the thermal parameters and the temperature structure of the model to agree with different geothermal heat flow models. We use three different heat flow models, one from machine learning, one from a spectral analysis of magnetic data and another one which is compiled from a similarity study with tomography data.

For the latter, a new shear wave tomography model of Greenland is used. Vs-depth profiles from Greenland are compared with velocity profiles from the US Array, where a statistical link between Vs profiles and surface heat flow has been established. A similarity function determines the most similar areas in the U.S. and assigns the mean heat-flow from these areas to the corresponding area in Greenland.

The geothermal heat flow models will be further used to discuss the influence on ice sheet dynamics by comparison to friction heat and viscous heat dissipation from surface meltwater.

How to cite: Wansing, A., Ebbing, J., Lösing, M., Lebedev, S., Celli, N., Karlsson, N. B., and Solgaard, A.: Implications for the lithospheric structure of Greenland by applying different heat flow models, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-10689, https://doi.org/10.5194/egusphere-egu21-10689, 2021.