A new 3D lithosphere model, interpreting combined seismic tomography and gravity data, describes
the lithosphere structure in terms of thermal and compositional variations. It depicts a strong correlation
between lithospheric thickness and tectonic evolution stages of the region.
For instance, ancient Archean cratons (Siberia and the eastern Fennoscandian Shield part) preserve
thick (more than 200 km) lithospheric keels formed as a result of early melt depletion and stabilization.
The apparent southward offset of the Siberian keel relative to earlier reconstructions suggests later
modification, possibly linked to Proterozoic collision or Mesozoic plume–rift interactions.
Thick lithosphere also underlays the Timan–Pechora block (Fig.1,
Fig. 4),
supporting its interpretation as a composite tectonic unit stabilized in Paleozoic.
This provides evidence that lithospheric thickening may also occur not only in ancient domains but also
in younger collisional systems. An intermediate (160–180 km) mechanically strong and cold lithosphere under northeastern
Barents Sea is consistent with a Proterozoic–Paleozoic subcontinental block in the Arctic basement mosaic.
The major Hercynian lithospheric structure of the Ural Orogen bounds the thick East European Craton
and the thinner, thermally modified West Siberian Plate that formed on a Paleozoic basement and was subject
to rifting and plume-driven tectonic activity in Mesozoic; thermal and density slices depict potential asthenospheric
mantle upwellings contributing to its present lithospheric structure.
East of the Verkhoyansk Range, the lithosphere is thin (<100 km) and tectonically dynamic across the
Chukotka Terrane, Anadyr–Koryak Fold Belt, and Kamchatka arc domains, shaped by Phanerozoic subduction,
terrane accretion, slab rollback (a “cold” slab trace in the thermal field can be seen in Fig. 3
under Kamchatka), and ongoing arc magmatism. These processes that inhibit lithospheric stabilization.
Overall, the strong lateral contrasts in the thermal and compositional lithospheric structure of northern
Eurasia are caused by the interaction of four fundamental processes in lithosphere formation: Archean craton
stabilization, Paleozoic orogenesis stages, Mesozoic plume–rift stage, and Pacific subduction.
The dataset includes the temperature and density values for six depth slices:
50, 100, 150, 200, 250 and 300 km from the Earth’s surface.
File names in
the temperature data zip-archive
t-XXXkm.txt, where XXX is the depth value in km.
File names in
the density data zip-archive
d-XXXkm.txt, where XXX is the depth value in km.
Description of data format.
