Rift migration explains continental margin asymmetry and crustal hyper-extension

The most remarkable and least understood structures associated with this process are up to 200 km wide areas of hyper-extended continental crust, which are partitioned between conjugate margins with pronounced asymmetry.

Using high-resolution thermo-mechanical modelling, we show that hyper-extended crust and margin asymmetry are produced by steady state rift migration. Our model challenges conventional ideas of rifted margin evolution, as it implies that during rift migration large amounts of material are transferred from one side of the rift zone to the other.

(a-e) The rift center moves laterally by more than 200 km during 20 Ma creating a wide margin (right) and a narrow margin (left). The wide margin is formed through sequentially active faulting towards the future ocean. Brittle faults are indicated with solid lines, ductile shear zones with dashed lines. (f) Asymmetry of the South Atlantic continental margins.


Cite as:

Brune, S., Heine, C., Perez-Gussinye, M., Sobolev, S.V., 2014. Rift migration explains continental margin asymmetry and crustal hyper-extension. Nature Communications 5. doi:10.1038/ncomms5014

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