Transition Zone from the Siberian Craton to the Verkhoyansk-Kolyma Folded System According to Seismic Data (Reference 3-DV Profile)

—From seismic data in the crust is revealed the structures of the Priverkhoyansk foredeep and local Backgraben (together with the adjacent part of the fold region) separated by the high-velocity massif of the Sette-Daban tectonic zone. The craton boundary slopes at an angle of about 15° beneath the folded crust, where is absent the lower crust layer with a velocity of 6.7–6.9 km/s, which is characteristic of the craton. The velocity in the entire crust of the studied part of the fold system is decreased to 6.2–6.3 km/s, versus 6.4–6.5 km/s for the craton, just like on Moho, from 7.9–8.0 to 8.3–8.4 km/s, respectively. The model is consistent with the views about the passive continental margin of the Siberian craton subjected to Mesozoic folding.