Geology - Sedimentology

Sedimentary budgets: concept, methods and integration in basin analysis on a land-sea continuum In a given sediment compartment , the sedimentary budget consists in evaluating sedimentary inputs, transfers and exports, and equating them to the net gain or loss over a specified period of time Sedimentary budgets are very widely used in geosciences. when integrated on a larger scale, they offer the possibility of acquiring a global vision of sedimentary systems.

Coastal systems such as deltas are vulnerable to sea-level rise and erosion. The stability of deltas depends on the sedimentary input produced in the watershed, which is strongly impacted by climatic and anthropogenic factors, whose variations and increasing pressure lead to problems of resource management (aquifers) and land-use planning (bank instability, flood management, etc.). In order to predict the impact of different environmental change scenarios and thus enable the implementation of appropriate local policies, it is essential to have modeling tools capable of integrating the various hydroclimatic and anthropogenic parameters and their temporal evolution...

In the current drive to find ways to produce inexpensive, green hydrogen, the natural hydrogen found underground is attracting growing interest as a component of a new energy mix. In Mali, the Bourakebougou field is the emblematic benchmark for natural underground hydrogen accumulations of this type today: 25 exploratory boreholes have demonstrated its presence in high concentrations (98 mol%), both in a geological reservoir located around one hundred meters below the surface and in other reservoirs at greater depths. In order to better characterize these reservoirs and the hydrogen retention and preservation processes at play, PhD research was conducted at IFPEN, in partnership with the field operator Hydroma...

For the last ten years or so, geologists have been fascinated by the natural hydrogen (H2) emitted within “cratons”, in the heart of continents. While its presence in subsurface has been identified in many places around the globe, it remains to be ascertained whether the use of this decarbonized energy source is likely to be economically viable. To answer this question and then identify the drilling sites with the greatest potential, large-scale quantification of this resource requires the use of modelling. (...) This PhD research set about examining the issue, taking as its subject the North American Midcontinent Rift System (MRS) composed of ancient rocks (over 1 billion years old) and extending over thousands of kilometers.

Pollutant transport in soils is directly dependent on the heterogeneity of the media present (topology, structure, etc.), which itself is heavily impacted by certain human activities, such as agriculture, industrial operations and mining. The precise description of this phenomenon, across all time scales, can thus prove complex. Yet it is important when it comes to tackling major challenges, such as efficient waste water treatment, or providing access to high-quality drinking water to as many people as possible. In this context, IFPEN’s researchers have been working on methods to gain a better understanding of how pollutants are transported in the underground environment.

Underground reservoir modeling in essential for many applications: aquifer management, underground compound or energy storage, mineral and energy resource recovery (e.g., geothermal energy). Modeling makes it possible to optimize resource management while minimizing societal and environmental risks. However, in order to be efficient, this modeling must be multiscale, and IFPEN’s research teams are therefore guided by this requirement.

Peatlands only occupy 3% of the earth’s surface but contain more than 25% of the organic carbon stored in the surface layers of the subsoil. Plant matter accumulates slowly there and undergoes a slow decomposition process under the effect of a water-saturated, oxygen-poor environment. Therefore the peat can still decompose and is particularly vulnerable to environmental changes...

Coastal sedimentary basins evolve under the effect of interactions between, on the one hand, hydroclimatic processes taking place in catchment areas, and on the other hand coastal marine processes that remodel the coastline. The evolution of these environments is naturally controlled by the climate, over different time periods (ranging from tens of years to thousands of years), through variations in sedimentary flows and erosion...