Circum-Arctic Lithosphere Evolution
CONTAINS OPEN ACCESS
Tectonics of the Laptev Shelf, Siberian Arctic
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Published:January 01, 2018
Abstract
The Laptev Sea in the Siberian Arctic represents a unique tectonic junction of an active spreading ridge, the Gakkel Ridge in the Eurasian oceanic basin, with the Siberian Arctic continental margin. New long-offset seismic profiles acquired in recent years provide a reliable basis for deciphering the structural and seismic stratigraphic characteristics of the Laptev Rift System. The tectonic development of the Laptev Shelf represents a sequence of four phases controlled by relative plate movements: (1) intense brittle normal faulting (an initial rifting or stretching phase) affected the entire shelf in the Late Cretaceous(?)–Paleocene(?); (2) a thinning/exhumation phase resulted in exhumation of the lower continental crust and probably upper mantle in the western part of the rift system – this phase is inferred to have occurred during the Late Paleocene to Early Eocene, preceding and accompanying continental break-up in the Eurasia Basin; (3) a stalled rift phase characterized by either a dramatically reduced rate of extension, or a non-extension/compression regime controlled by major reorganization of the plate movements – the onset of this fourth phase is inferred to coincide with the initiation of seafloor spreading in the southern Eurasia Basin at around 53–50 Ma; and (4) reactivation of the rifting in the mid-Miocene (a second rift phase).
- Arctic Ocean
- Arctic region
- Asia
- brittle deformation
- Cenozoic
- compression tectonics
- continental crust
- continental margin
- continental shelf
- cratons
- Cretaceous
- crust
- crustal thinning
- deformation
- Eocene
- Eurasia Basin
- exhumation
- extension tectonics
- faults
- fold belts
- geophysical methods
- geophysical profiles
- geophysical surveys
- grabens
- horsts
- Laptev Sea
- lower crust
- lower Eocene
- mantle
- Mesozoic
- Mid-Arctic Ocean Ridge
- middle Miocene
- Miocene
- movement
- Neogene
- normal faults
- ocean basins
- Paleocene
- Paleogene
- plate tectonics
- reactivation
- rift zones
- rifting
- sea-floor spreading
- seismic methods
- seismic profiles
- seismic stratigraphy
- Siberia
- stratigraphy
- surveys
- systems
- tectonics
- Tertiary
- Upper Cretaceous
- upper mantle
- upper Paleocene
- Laptev Shelf