East European Sedimentary Basins Stewed Over an Ancient Mantle Upwelling
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Date:
29/06/2023
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Time:
4:00 pm
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A strong negative anomaly of seismic wave velocities at the core-mantle boundary (the Perm Anomaly, PA) beneath the East European (EE) platform is attributed to a remnant deep mantle upwelling. The interaction between the upwelling and the EE lithosphere in the geological past and its resulting surface manifestations are still poorly understood. Using mantle plume modelling and global plate motion reconstructions, we show here that the EE lithosphere has been situated over the weakening PA upwelling for about 150-200 million years. As the EE platform moved above PA in post-Jurassic times, the vertical tectonic movements recorded in sedimentary hydrocarbon-rich basins show either hiatus/uplift or insignificant subsidence. Analytical modelling of heat conduction through the lithosphere demonstrates that the basins have been thermally stewing above PA upwelling, creating suitable conditions for hydrocarbon maturation. This establishes a profound relationship between mantle plume dynamics, basin evolution, and hydrocarbon generation.