Sedimentological and tectonostratigraphic models for synrift to post-rift transitions : the case of the Upper Jurassic to Lower Cretaceous of the Norwegian Sea
Stratigraphic rift-basin successions have promoted a tremendous amount of tectonostratigraphic studies during the last decades. However, the syn-rift to post-rift transition is still a matter of debate. This PhD thesis presents the case of the Norwegian Sea continental margin, intending to reconstru...
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Other Authors: | , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
HAL CCSD
2021
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Subjects: | |
Online Access: | https://theses.hal.science/tel-03584293 https://theses.hal.science/tel-03584293/document https://theses.hal.science/tel-03584293/file/TH2021GRIMEROMAIN.pdf |
Summary: | Stratigraphic rift-basin successions have promoted a tremendous amount of tectonostratigraphic studies during the last decades. However, the syn-rift to post-rift transition is still a matter of debate. This PhD thesis presents the case of the Norwegian Sea continental margin, intending to reconstruct the evolution of depositional environments during the syn-rift and post-rift stages. The Norwegian Sea has been chosen for its atypically wide terrace domain across which a tremendous amount of data has been acquired, but never comprehensively integrated. In this study, the identification of fifteen stratigraphic sequences (S1 to S15), combined with a reappraised dinoflagellate cyst zonation, enables the studied stratigraphic interval to be divided into three major periods with (i) the syn-rift period (S1 to S7, dated from the Middle Bathonian to the Middle/Late Berriasian), (ii) the transitional rift-sag period (S8, dated from the Middle/Late Berriasian to the Aptian/Albian boundary) and (iii) the post-rift period (S9 to S15, dated between the Aptian/Albian boundary and the Early Coniacian). Those three major periods fit well into the Atlantic multiphased rift evolution. The syn-rift period is marked by an intense tectonic activity during which coarse-grained deltas have conjointly developed with wave-dominated coasts. The rift-sag stage is a transitional period during which tectonic activity waned between the terrace and the platform domains while fostered the development of deep-water turbidite lobe complexes. The rift-sag phase most probably corresponds to a period of migration of the deformation from the terrace domain to the deep domain. The post-rift stage is defined by a phase of tectonic quiescence coevally with the deposition of thick offshore marine mudstone successions. Les successions stratigraphiques de bassins de type rift ont fait l'objet d'un nombre considérable d'études tectonostratigraphiques au cours des dernières décennies. Cependant, la transition entre la période syn-rift et la période ... |
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