Control of the Paleogene sedimentary record of the Anglo-Paris Basin by both the Iceland mantle plume and the Massif Central hotspot

Abstract

We test here an earlier hypothesis of ours that the Massif Central hotspot, combined with the Iceland mantle plume, exercised first-order control of the Paleogene sedimentary record in the Anglo-Paris Basin. The Anglo-Paris Basin formed a southwestern arm of the Paleogene North Sea. Correlation of Paleogene depositional sequences across the North Sea Basin suggests that control of the sedimentary record in the Anglo-Paris Basin was exercised by both hotspots. The Cretaceous chalk in the basin was uplifted in two main episodes during the early and middle Paleocene. Also during the Paleocene, there was broadly synchronous vertical uplift of the unconformably underlying Mesozoic rocks on both the northwest and southeast flanks of the Anglo-Paris Basin. The resulting opposed regional dips are still obvious at the present day. This regional tilting of the Mesozoic into the Paleogene basin was caused by uplift by the early Iceland plume to the northwest, and by uplift associated with the inception of the early Massif Central hotspot to the southeast. Crustal shortening played a minor role in these hotspot-created vertical movements. In the Paleocene-early Eocene, high-frequency changes in relative regional sea-level in the Anglo-Paris Basin were controlled by apparently synchronous time-dependent behaviour of the Iceland and Massif Central hotspots. In contrast, from the early Eocene onwards, control of sea-level appears to have been exercised separately, with the two hotspots pulsing at different times.