Abstract
AbstractFracture pattern development has been a challenging area of research in the Earth sciences for more than 100 years. Much has been learned about the spatial and temporal complexity inherent to these systems, but severe challenges remain. Future advances will require new approaches. Chemical processes play a larger role in opening‐mode fracture pattern development than has hitherto been appreciated. This review examines relationships between mechanical and geochemical processes that influence the fracture patterns recorded in natural settings. For fractures formed in diagenetic settings (~50 to 200 °C), we review evidence of chemical reactions in fractures and show how a chemical perspective helps solve problems in fracture analysis. We also outline impediments to subsurface pattern measurement and interpretation, assess implications of discoveries in fracture history reconstruction for process‐based models, review models of fracture cementation and chemically assisted fracture growth, and discuss promising paths for future work. To accurately predict the mechanical and fluid flow properties of fracture systems, a processes‐based approach is needed. Progress is possible using observational, experimental, and modeling approaches that view fracture patterns and properties as the result of coupled mechanical and chemical processes. A critical area is reconstructing patterns through time. Such data sets are essential for developing and testing predictive models. Other topics that need work include models of crystal growth and dissolution rates under geological conditions, cement mechanical effects, and subcritical crack propagation. Advances in machine learning and 3‐D imaging present opportunities for a mechanistic understanding of fracture formation and development, enabling prediction of spatial and temporal complexity over geologic timescales. Geophysical research with a chemical perspective is needed to correctly identify and interpret fractures from geophysical measurements during site characterization and monitoring of subsurface engineering activities.
Highlights
Chemical processes play a larger role in opening‐mode fracture pattern development than has hitherto been appreciated
This review examines relationships between mechanical and geochemical processes that influence the fracture patterns recorded in natural settings
We show that progress in fracture pattern interpretation and prediction can be enhanced by new observational, experimental, and modeling approaches that place emphasis on the ubiquitous chemical processes affecting fractures in diagenetic settings
Summary
Accurate and testable predictions of fracture patterns in rock are essential to understand many societally important processes in the Earth and for effective management of subsurface engineering operations. The role of existing fractures in transporting reactive fluids and of fluids modifying fractures has been reviewed (e.g., National Research Council, 1996; Ord et al, 2016; Steefel & Lasaga, 1994; Steefel & Lichtner, 1998; Steefel et al, 2005, 2015; Taron et al, 2009; Xiao et al, 2018), this previous work does not cover recent developments on the role that chemistry plays in natural fracture pattern interpretation and development These include breakthroughs and opportunities in using chemical evidence to unravel fracture timing and how patterns develop and rock mechanical properties evolve. Basic scientific investigations are needed to improve our ability to accurately predict the properties of fracture systems—one of the most refractory practical problems in subsurface science
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
