Nov 2023
Abstract
The flow properties of reservoir rocks are controlled by inter-related factors including the depositional facies (original textures and mineralogy), fluid-rock interactions (diagenesis) and fracturing. These often result in complex, multiple pore systems that are variously interconnected and difficult to predict. The practical challenge is to quantify the distribution of flow properties across the reservoir, usually with scarce subsurface data, that, if available, are only representative of very small mm- to cm-scales (core-samples). We developed a research and innovation program dedicated to build, apply, and validate new workflows for multi-scale quantification of the subsurface flow properties. It is based on a combination of observational, experimental, and numerical methodologies, covering the conventional reservoir types (e.g., carbonates, silici-clastics) and the non-conventional aquifers (e.g., igneous, metamorphic). The long-term impact of this R&I program is to improve the utilisation and the sustainability of the subsurface and its resources.
Representative surface exposed geologic objects (outcrops) are invaluable as they provide access to the vertical and lateral continuity of heterogenous reservoir facies. They allow for 3D mapping of the sedimentary architecture, structural elements, and flow properties. First, a photogrammetric model is achieved to capture the 3D image of the outcrops and to georeference the field in-situ observations (e.g., sedimentology, structural geology, geophysics, permeability) and sampling. The interpretation of such models leads, in a second step, to the construction of static geo-models that – if representative – can be proposed as analogues to their subsurface equivalent reservoirs. They can also be used as digital tools for testing scenarios and for eLearning education. Rock samples taken from representative geo-referenced outcrops and/or well cores are analysed through a tailor-made multi-scale multi-physics (MsMp) approach, including geological (petrography, mineralogy), geophysical (petro-accoustics) and petrophysical (pore space, flow) quantitative characterisation. Results of this analytical approach are integrated with well-logging data and/or fed to the (outcrops) 3D models. Dynamic reactive core-flooding (e.g., dissolution, mineral precipitation) is then applied on representative samples (mm- to cm-scale) to analyse specific fluid-rock interaction processes and quantify their impacts on the reservoirs at different scales. This is coupled with geochemical reactive transport simulations that are perfectly constrained by the experiments. Henceforth, the numerical solution can be used instead of the experimental one and can be scaled up to the dimensions of the reservoir cells. Guided numerical modelling follows based on precise, up-scalable reservoir characteristics. First, a conceptual geological model is developed based on field observational and lab experimental methodologies. These include the developed 3D outcrop models and MsMp results. The conceptual geological model is thereafter simplified into a 3D static model encompassing the principal elements that will allow building up a dynamic reactive model allowing flow and transport reactive simulations. The obtained simulations are coherent with the core-flooding experimental and modelling results. They are furthermore validated with existing dynamic data (e.g., production data). The validation process includes history-matching to test and further calibrate the model. The validated model can be used as a tool to test several applications of the subsurface, quantify their impacts and associated risks.
Bio
Fadi Henri NADER is currently a research project leader and geosciences expert at IFPEN Energy Resources (France) and Chair Professor of “Multiscale Fluid-Rock Interactions” in the Department of Earth Sciences at Utrecht University (the Netherlands).
Prof. NADER has more than 20 years of experience in fundamental and applied Earth sciences research (published more than 100 journal articles). He is expert in sedimentology, characterization and modelling of sedimentary basins and reservoirs/aquifers (clastics and carbonate rocks, fluid flow, diagenesis), integrated stratigraphy, seismic interpretation, structural geology and geochemistry as well as karst and speleothems studies. He graduated from the American University of Beirut (Lebanon) in Geology (BSc., MSc. -1994/2000), got his PhD at the KU Leuven University (Belgium, 2003), and HDR (Habilitation de Direction de la Recherche) at the Paris-Sorbonne University France (2015), appointed professor at Utrecht University in 2019.