IMIS | Flanders Marine Institute

Flanders Marine Institute

Platform for marine research


Publications | Institutes | Persons | Datasets | Projects | Maps
[ report an error in this record ]basket (0): add | show Printer-friendly version

How plate tectonics is recorded in chalk deposits along the eastern English Channel in Normandy (France) and Sussex (UK)
Duperret, A.; Vandycke, S.; Mortimore, R.N.; Genter, A. (2012). How plate tectonics is recorded in chalk deposits along the eastern English Channel in Normandy (France) and Sussex (UK). Tectonophysics 581: 163-181.
In: Tectonophysics. ELSEVIER SCIENCE BV: New York; London; Amsterdam. ISSN 0040-1951, more
Peer reviewed article  

Available in  Authors 
    VLIZ: Open Repository 279341 [ OMA ]

Author keywords
    Chalk; Meso scale fracturing; Paleostress; Lithostratigraphy; TheEastern English Channel; Anglo-Paris basin

Authors  Top 
  • Duperret, A.
  • Vandycke, S.
  • Mortimore, R.N.
  • Genter, A.

    Intra-plate stresses that occurred in the Anglo-Paris Basin and English Channel during Upper Cretaceous and Cenozoic times are a consequence of the convergence between Eurasia and Africa and the opening of the North Atlantic area. This geodynamic re-organisation is recorded on each side of the English Channel, with the emergence of regional structures such as the the Weald-Artois anticline and the reactivation of large-scale strike-slip faults. We analyse the Anglo-Paris Basin Chalk fracture system, on each side of the eastern English Channel, using a set of 1600 meso-scale fractures data collected on coastal chalk cliffs in Normandy (NW France) and Sussex (UK). Meso-scale fracture system is precisely dated using chalk lithostratigraphy correlations within the basin. Moreover, an inversion method is used on fault slip data to evidence a paleostress chronology in the Anglo-Paris Basin. Three main Upper Cretaceous extensive events, characterized by normal faults and jointing are recorded in Normandy and two Cenozoic compressive and extensive events with strike-slip and normal faults appear in Sussex. Paleostress records vary on each part of the eastern English Channel. The meso-scale fracture system is thus used to better define the type of relationship between meso-scale and large-scale brittle deformation in the Chalk during Meso-Cenozoic. A first NE-SW extension is recorded in Normandy in relation with local anticlines structures and related to the Lower Rhine graben opening. A second event is a WNW-ESE extension of local origin in relation with the subsidence axis of the Paris Basin. The third event is a NNE-SSW extension, well marked in Normandy and related to the activation of E-W normal faults in the western approaches of the English Channel. This event is also recorded in Sussex and reactivates locally older fractures in strike-slip. The Oligocene N-S compression/E-W extension related to the Pyrenean tectonics and the last E-W extension relative to the North Sea graben opening are well recorded in Sussex, but not in Normandy. Recent far-field stresses developed in the NW European platform are focused on deep crustal structures like the Artois hills and the Cotentin areas in France. These structures act as a stress barrier by protecting the Normandy Chalk from recent far-field stresses. On the contrary, recent far-field stresses are easily recorded by meso-scale brittle deformation on the folded Chalk in Sussex.

All data in IMIS is subject to the VLIZ privacy policy Top | Authors