A review of biomineralization mechanisms and theories in MICP and EICP

Biomineralization via calcium carbonate precipitation, which is induced by microbial or enzymatic activity, lies at the intersection of biology, geochemistry and engineering. It offers sustainable solutions for soil stabilization, environmental remediation and concrete self-healing. This review summarizes the current understanding of the mechanisms and theoretical frameworks of MICP/EICP, paying particular attention to the pore-scale behaviors elucidated by microfluidic studies. First, it introduces the biomineralization microfluidic platforms from an evolutionary perspective, highlighting their ability to visualize bacterial transport, reaction fronts, and CaCO 3 precipitation, as well as crystal growth, morphology, and spatial distribution in pores and fractures. Then, some key biochemical processes are comprehensively discussed and outlined from bacterial contributions to crystal growth and distribution. It further links crystal nucleation and growth theories, particle-scale biocementation concepts, and models coupling bacterial behavior with bio-chemo-hydro-mechanical upscaling toward continuum-scale descriptions. In addition, current research gaps and future directions are identified in terms of multiphysics microfluidics, coordinated multiscale experimentation, and more efficient predictive modeling, emphasizing the need for cross-disciplinary collaboration to enable robust and versatile field implementations of biomineralization technology.