The current accepted tectonic model for the area favors the hypothesis of a long-lasting rifting phase occurring between the Permian and the Jurassic. This model fits well with the general plate tectonic reconstruction relating this rifting phase with the opening of the Neo-Tethys Ocean. However, in Tunisia, the sedimentary record of the Permian is strongly affected by a series of unconformities related with a “late” Hercynian Orogeny event. These erosional events make the Permian record very partial and geodynamic reconstruction difficult to establish with certainties. 

A reinvestigation of a subsurface dataset, combined with surface data collected in outcrops, attested the absence of rifting-like deformation in the Permian and in the Triassic sediments at the considered mega-regional scale. Instead, the Permian and the Triassic seems to have behaved more like sag basins, locally affected by successive shortening events generating large-scale subtle undulations persisting until the end of the Jurassic. 

Work published

Identifying Local vs. Regional Drainage using multiproxy provenance tracers - A case study from within the Moroccan Triassic

James Lovell-Kennedy, Emmanuel Roquette, Jonathan Redfern, Stefan Schröder, & Rémi Charton 

in Journal of African Earth Sciences, available online February 2023

Open Access

+2 manuscripts in preparation

Part 1: Exhumation data

Low-temperature thermochronology studies revealed major exhumation events affecting domains in the hinterland of the Central Atlantic margins, where Palaeozoic and/or Precambrian basement is exposed. Thus, domains traditionally assumed to be stable since at least the Variscan and juxtaposed to subsiding Meso-Cenozoic basins, appear to be affected by km-scale vertical movements during the Atlantic rifting and after the Early Jurassic breakup in the Central Atlantic. In this project, we investigate the extent and the magnitude of these motions along the NW African margin (Morocco-Mauritania-Senegal). 

Work published

New evidence of 'Anomalous' Vertical Movements along the hinterland of the Atlantic NW African margin

Mohamed Gouiza, Giovanni Bertotti, Rémi Charton, K. Haimoudane, I. Dunklan, & A. Anczkiewicz

in Journal of Geophysical Research Solid Earth, Volume 124 of November 2019

Part 2: Landscape Evolution Modelling

Paleo-altimetry, stratigraphy, and sediment budgets may be evaluated with numerical models commonly refered to as ‘Landscape Evolution Models’ (LEMs).  Source-to-sink studies have limitations: the spatial and temporal resolution of each component for instance or the quality of the sedimentary record. This renders the examination of past source-to-sink systems a challenging task, however the range of possible outcomes can be partially addressed by building multiple models using process-based modelling tools such as LEMs. In NW Africa, the distribution of eroded sediments in the rifted margin is controlled by the drainage systems connected to the hinterland. However, most of paleo-river systems were not fossilised or are not exposed, resulting in a lack of data for their size, sediment flux, and entry-point position. In order to better understand Moroccan Mesozoic source-to-sink systems, we use the LEM ‘pyBADLANDS’ code (Salles et al., 2018). We input the timing, location and amplitude of exhumation events, as documented by low-temperature thermochronology data. 

Work published

+2 manuscripts in preparation

The North Africa Research Group (NARG) Morocco team works on multiple integrated regional studies focussed on the eastern Central Atlantic Margin. The studies form the base for a large Source to Sink study. The project is made possible by the outstanding outcrop quality, well and seismic data offshore supplied by ONHYM and strong collaboration with major E&P companies and local stakeholders.

Methods: Geology, Ichnology, Foraminifera, Carbonates, Ammonoidea, Sequence Stratigraphy, Biostratigraphy, Geochronology, Carbon Isotopes, TOC, Provenance, Stratigraphy, Seismic Interpretation, Salt Tectonics, Calcareous Nannofossils

Work published

Syn-depositional Mesozoic siliciclastic pathways on the Moroccan Atlantic margin linked to evaporite mobilisation

Rémi Charton,  Christian Kluge, David Fernández-Blanco, Aude Duval-Arnould, Orrin Bryers, Jonathan Redfern , &  Giovanni Bertotti 

in Journal of Marine and Petroleum Geology, Volume 128 of June 2021 (see the Pre-print version)

Open Access

Early post-rift depositional systems of the Central Atlantic: Lower and Middle Jurassic of the Essaouira-Agadir Basin, Morocco.

Aude Duval Arnould, Stefan Schröder, Rémi Charton, Rémi Joussiaume, Philippe Razin, & Jonathan Redfern

in  Journal of African Earth Sciences, Volume 178 of June 2021

Anticline growth by shortening during crustal exhumation of the Moroccan Atlantic margin 

David Fernández-Blanco, Mohamed Gouiza, Rémi Charton, Christian Kluge, J. Klaver, K. Brautigam, & Giovanni Bertotti 

in Journal of Structural Geology,  Volume 140 of November 2020 (see the Pre-print version)

Open Access

The project was supervised by Dr. P.Y. Collin of the UMR 6282 at the University of Burgundy (Dijon) and funded by the Bureau de Recherches Géologiques et Minières (BRGM).   

For the BRGM, the Paris Basin (France) is a potential location for deep geological storage of CO2. The “Oolithe Blanche” Formation (Bathonian, Middle Jurassic) and its lateral equivalent formations are currently studied for this purpose. The site suitability as a storage zone depends on its petrophysical properties (porosity/permeability), which are influenced by compaction and cementation.

Several sets of fluids (meteoric, marine or mixed) have circulated within these mainly oolitic formations at different times during their diagenetic history. To constrain the composition and the origin of these fluids, analyses of cement phases were conducted across the Paris Basin. From the northwestern Bathonian fringe in Normandy down to Poitou and Centre, nine sedimentological sections were selected in order to provide the base of this work. Forty thin sections were made out of these outcrops and analysed by microscopy, staining and cathodoluminescence.

Bathonian sediments have undergone the three diagenetic stages: eogenesis, mesogenesis and telogenesis. Parent fluids of mesogenetic cements are widely compared on the eastern side of the basin (geochemistry, ferrous content, luminescence) but not on the opposite side. This work shows that mesogenetic phases are clearly different across the Paris Basin. However, parent fluids origins, ages and paths were not well constrained.

Work published

Reactive transport modelling of carbonate cementation in a deep saline aquifer, the Middle Jurassic Oolithe Blanche Formation, Paris Basin, France.

Sophie Violette, Pierre-Yves Collin, Vincent Lagneau, Fabien Aubertin, Yasin Makhloufi, Rémi Charton, & Françoise Bergerat 

in Comptes Rendus Geoscience, Volume 348 of September-October 2016 

Open Access