Premium
The Effect of Mineral Dissolution on the Effective Stress Law for Permeability in a Tight Sandstone
Author(s) -
Ma Jin,
Querci Lorenzo,
Hattendorf Bodo,
Saar Martin O.,
Kong XiangZhao
Publication year - 2020
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2020gl088346
Subject(s) - dissolution , permeability (electromagnetism) , geology , dolomite , porosity , cement , mineralogy , calcite , brine , materials science , geotechnical engineering , composite material , chemical engineering , chemistry , organic chemistry , membrane , engineering , biochemistry
We present flow‐through experiments to delineate the processes involved in permeability changes driven by effective stress variations and mineral cement dissolution in porous rocks. CO 2 ‐enriched brine is injected continuously into a tight sandstone under in situ reservoir conditions for 455 hrs. Due to the dolomite cement dissolution, the bulk permeability of the sandstone specimen significantly increases, and two dissolution passages are identified near the fluid inlet by X‐ray CT imaging. Prereaction and postreaction examinations of the effective stress law for permeability suggest that after reaction, the bulk permeability is more sensitive to pore pressure changes and less sensitive to effective stress changes. These observations are corroborated by Scanning Electron Microscopy and X‐ray CT observations. This study deepens our understanding of the effect of mineral dissolution on the effective stress law for permeability, with implications for characterizing subsurface mass and energy transport, particularly during fluid injection/production into/from geologic reservoirs.