Formation of intracratonic basins by lithospheric shortening and phase changes: a case study from the ultra‐deep East Barents Sea basin
Abstract The origin of large subsidence in intracratonic basins is still under debate. We propose a new and self‐consistent model for the formation of those basins, where lithospheric shortening/buckling triggers metamorphism and densification of crustal mafic heterogeneities. We use a forward therm...
| Published in: | Terra Nova |
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| Main Authors: | , , , , |
| Other Authors: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
2013
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1111/ter.12057 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fter.12057 https://onlinelibrary.wiley.com/doi/pdf/10.1111/ter.12057 |
| Summary: | Abstract The origin of large subsidence in intracratonic basins is still under debate. We propose a new and self‐consistent model for the formation of those basins, where lithospheric shortening/buckling triggers metamorphism and densification of crustal mafic heterogeneities. We use a forward thermo‐mechanical finite element technique to evaluate this mechanism for the typical example of the East Barents Sea basin ( EBB ) where a very large and compensated subsidence, accommodating an up to 20‐km‐thick sediment succession, is observed. The lower crust in the dynamic model is modelled with petrologic‐consistent densities for a wet mafic gabbroic composition that depend on pressure and temperature taking into account dehydration at high PT conditions. The model successfully explains the main characteristics of the EBB , notably the large anomalous and fast subsidence during the Late Permian–Early Triassic, its present‐day geometry and the absence of a significant gravity anomaly. |
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