English

Uncertainty Quantification of Fluid Leakage and Fault Instability in Geologic CO2 Storage

Geophysics 2024-11-14 v1 Data Analysis, Statistics and Probability

Abstract

Geologic CO2_2 storage is an important strategy for reducing greenhouse gas emissions to the atmosphere and mitigating climate change. In this process, coupling between mechanical deformation and fluid flow in fault zones is a key determinant of fault instability, induced seismicity, and CO2_2 leakage. Using a recently developed methodology, PREDICT, we obtain probability distributions of the permeability tensor in faults from the stochastic placement of clay smears that accounts for geologic uncertainty. We build a comprehensive set of fault permeability scenarios from PREDICT and investigate the effects of uncertainties from the fault zone internal structure and composition on forecasts of CO2_2 permanence and fault stability. To tackle the prohibitively expensive computational cost of the large number of simulations required to quantify uncertainty, we develop a deep-learning-based surrogate model capable of predicting flow migration, pressure buildup, and geomechanical responses in CO2_2 storage operations. We also compare our probabilistic estimation of CO2_2 leakage and fault instability with previous studies based on deterministic estimates of fault permeability. The results highlight the importance of including uncertainty and anisotropy in modeling of complex fault structures and improved management of geologic CO2_2 storage projects.

Keywords

Cite

@article{arxiv.2411.08039,
  title  = {Uncertainty Quantification of Fluid Leakage and Fault Instability in Geologic CO2 Storage},
  author = {Hannah Lu and Lluis Salo-Salgado and Youssef M. Marzouk and Ruben Juanes},
  journal= {arXiv preprint arXiv:2411.08039},
  year   = {2024}
}