Modeling the evolution of spectral induced polarization during calcite precipitation on glass beads

Philippe Leroy (1) , Li Shuai (1) , Damien Jougnot (2) , André Revil (3) , Yuxin Wu (4)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
2 UPMC - Université Pierre et Marie Curie - Paris 6
3 ISTerre - Institut des Sciences de la Terre
4 LBNL - Lawrence Berkeley National Laboratory [Berkeley]

When pH and alkalinity increase, calcite frequently precipitates and hence modifies the petrophysical properties of porous media. The complex conductivity method can be used to directly monitor calcite precipitation in porous media because it is very sensitive to the evolution of the pore structure and its connectivity. We have developed a mechanistic grain polarization model considering the electrochemical polarization of the Stern layer surrounding calcite particles. This model depends on the surface charge density and mobility of the counter-ions in the Stern layer. Our induced polarization model predicts the evolution of the size of calcite particles, of the pore structure and connectivity during spectral induced polarization experiments of calcite precipitation on glass beads pack. Model predictions are in very good agreement with the complex conductivity measurements. During the first phase of calcite precipitation experiment, calcite crystals growth, and the inverted particle size distribution moves towards larger calcite particles. When calcite continues to precipitate and during pore clogging, inverted particle size distribution moves towards smaller particles because large particles do not polarize sufficiently. The pore clogging is also responsible for the decrease of the connectivity of the pores, which is observed through the increasing electrical formation factor of the porous medium.

Domaines: Géochimie

Philippe Leroy, Li Shuai, Damien Jougnot, André Revil, Yuxin Wu. Modeling the evolution of spectral induced polarization during calcite precipitation on glass beads. 4th International Workshop on Induced Polarizatio, Jun 2016, Aarhus, Denmark. ⟨hal-01309313⟩