Maxime DUCOUX

Architecture and thermicity of hyperextended rift system integrated in the Pyrenean orogenic belt

Supervisors:
Calassou Sylvain – Total, CSTJF, Pau,
Masini Emmanuel – Total, M&U, Grenoble

Major Results

  1. Understood the architecture of the hyperextended rift system associated with pre-kinematic decoupling layer, preserved in the Pyrenean range (extension with salt)
  2. Measured the thermal maturity of this hyperextended rift system.
  3. Thermal pattern documents the asymmetry of the rift system

Abstract

The aim of our study is to understand how the rifted margins are inverted and integrated in orogens during early inversion processes. In order to resolve this topic, we must describe the architecture of the former rifted margins. We looked the tectono-sedimentary record, deduced from the analysis of fault-sediment relationships and subsidence and thermal maturity of rift basin development, in order to unravelling the rifting processes. We used the Pyrenean range as study case, because a Cretaceous hyperextended rift system is preserved and integrated in this orogen.
Rifting event in Pyrenees is associated with a pre-rift decoupling layer (Upper Triassic evaporites) that play a significant role on the rift and orogen architecture. In the distal domain, along the main axis rift axis, the pre- and syn-rift sediments of the basin directly overlies exhumed mantle assisted by the efficiency of the decoupling layer. Associated with the thinning, the basin is also affected by a HT/LP metamorphism with maximum temperatures exceeded 500°C.

 

RAMAN thermometry and Vitrinite Reflectance measured in organic material suggest that the metamorphic event is only localized in pre- and syn-rift sediments. Post-rift sediments are preserved from metamorphism and may play the role of blanket for underlying sediments. Along the necking domain we show the development of the Arzacq Basin corresponding to a syn-rift rim-syncline previously attributed to sag basin. A basement-restricted north-dipping low-angle and long-offset normal fault leads the formation of this rim-syncline. This fault was revealed by dense seismic and well calibrations showing cut-offs of the top basement, sedimentary architecture (south-verging growth strata and migration of syn-rift depocentres toward the fault). We also show that the hyperextended domain is the first domain inverted and integrated in the orogen during the convergence.

Impact of geodynamics on fluid circulation and diagenesis of carbonate reservoirs in a foreland basin: Example of the Upper Lacq reservoir (Aquitaine basin, SW France).

Impact of geodynamics on fluid circulation and diagenesis of carbonate reservoirs in a foreland basin: Example of the Upper Lacq reservoir (Aquitaine basin, SW France).

Elias Bahnan, A., Carpentier, C., Pironon, J., Ford, M., Ducoux, M., Barré, G., Mangenot, X., Gaucher, E.C. (2020). Impact of geodynamics on fluid circulation and diagenesis of carbonate reservoirs in a foreland basin: Example of the Upper Lacq reservoir (Aquitaine basin, SW France), Marine and Petroleum Geology (2019).

keywords:Carbonate diagenesis, Pyrenees, Aquitaine foreland basin, Upper Lacq reservoirs, Fluid inclusions, Basin modeling, Dolomitization, Hydrothermal fluids

DOI: https://doi.org/10.1016/j.marpetgeo.2019.08.047

Hydrothermal fluid circulations in the western Pyrenees: new data on stable isotopes, in-situ gas analysis and fluid inclusions.

Hydrothermal fluid circulations in the western Pyrenees: new data on stable isotopes, in-situ gas analysis and fluid inclusions.

Barré, G., Elias Bahnan, A., Motte, G., Ducoux, M., Hoareau, G., Laurent, D., Gaucher, E.C. (2019) Hydrothermal fluid circulations in the western Pyrenees: new data on stable isotopes, in-situ gas analysis and fluid inclusions. E3S Web. Conf. 98, 4.

keywords:  Hydrothermal circulation, Western Pyrenees, H2S

DOI: https://doi:10.1051/e3sconf/20199801001

The Nappe des Marbres unit of the Basque‐Cantabrian Basin: the tectono‐thermal evolution of a fossil hyperextended rift basin.

The Nappe des Marbres unit of the Basque‐Cantabrian Basin: the tectono‐thermal evolution of a fossil hyperextended rift basin.

Ducoux, M., Jolivet, L., Callot, J-P., Lahfid, A., Aubourg, C. et al. (2019). The Nappe des Marbres unit of the Basque‐Cantabrian Basin: the tectono‐thermal evolution of a fossil hyperextended rift basin. Tectonics, American Geophysical Union (AGU), 2019, 38 (11), pp.3881-3915. ⟨insu-02288781⟩

keywords:  Pyrenean Belt, Eastern Basque‐Cantabrian Basin, structure, metamorphism, RSCM method, salt tectonics, Hyperextended Rift Basin

DOI: https://doi.org/10.1029/2018TC005348

Role of rift structural inheritance in orogeny highlighted by the Western Pyrenees case-study 

Role of rift structural inheritance in orogeny highlighted by the Western Pyrenees case-study

Gómez-Romeu, J., Masini, E., Tugend, J., Ducoux, M., Kusznir, N. (2019). Role of rift structural inheritance in orogeny highlighted by the Western Pyrenees case-study. Tectonophysics, Elsevier, 2019, 766, pp.131-150.

keywords:  Western Pyrenees, Rift structural inheritance, Flexural isostatically and structurally balanced cross-section

DOI: https://doi.org/10.1016/j.tecto.2019.05.022

PhD Thesis: Structure, thermicité et évolution géodynamique de la Zone Interne Métamorphique des Pyrénées.

PhD Thesis: Structure, thermicité et évolution géodynamique de la Zone Interne Métamorphique des Pyrénées.

Maxime Ducoux. Structure, thermicité et évolution géodynamique de la Zone Interne Métamorphique des Pyrénées. Sciences de la Terre. Université d’Orléans, 2017. Français. ⟨NNT : 2017ORLE2026⟩. ⟨tel-01887025⟩

keywords: Pyrenees, Structural study, HT-LP metamorphism, Raman thermometry, Thrust tectonics, Geodynamic model, Salt tectonics, Inheritance

DOI: https://tel.archives-ouvertes.fr/tel-01887025/document