Organic matter and clays: sedimentary origin, associated resources and reservoirs

Organic matter (OM) represents only a small part of the sedimentation. Unlike other deposited particles, it can evolve rapidly during burial by interacting with the grains of the host rock and producing fluids (gases and liquids) that will be very mobile. Because of its degradation by bacteria, its preservation depends on many parameters but above all on the fine grain size of the grains deposited at the same time. Thus, clays represent the most favourable environment for the preservation of OM, but their complex mineralogy makes them a particular material that will also be transformed during burial. The products of their interactions have of interest to the mining and then to the oil industry, of course, since these processes are at the origin of large series of coal and the production of hydrocarbons. But recently, studies have been increasingly interested in these two elements as tracers of the origin of sediments and as markers of burial, which is of major interest in understanding the filling of basins and their post-deposition evolution.

Sessions are organized around the sequence:
- Introduction
- Organic matter in sediments (origin and nature)
- Coals (formation and classification)
- Clays (origin and evolution with burial)
- Maturation of organic matter (transformations and interactions with clays)
- Unconventional resources (use of OM-rich clays)

These concepts will then be used to introduce basin modeling (deposition, geodynamic and post-depositional tectonic history, burial curves and thermal history), which will be covered in S4 in the Resource Evaluation module, "fluids" option.

Students should have a good knowledge of basin geology and sedimentology (S1 and S2 of Master's degree).

Knowledge of organic geochemistry may be a plus for acquiring the complex notions of the module.

Graded exercises punctuate the TD/TP sessions and an applied final exam will be carried out on a case study.