What is the significance of pore pressure in a saturated shale layer?

Julio Gonçalvès, Pauline Gueutin, G de Marsily, Philippe Cosenza, Sophie Violette

    Research output: Contribution to journalArticle

    29 Citations (Scopus)

    Abstract

    Electrostatic interactions, associated with negatively charged surfaces of clay minerals, produce a so-called "disjoining pressure" when diffuse layers overlap, i.e., at low porosity. Disjoining pressure is the pressure difference between the water in the clay pore space and that in a bulk solution at the same depth. Another widely used concept in clay-rocks is the "swelling pressure." It corresponds in fact to the macroscopic average of the disjoining pressure. This study proposes to determine the value of the swelling pressure of a natural material by a simple volume-averaging approach of the disjoining pressure, calculated for each clay mineral present in the material. The swelling pressure, which is dependent on the salinity of the pore fluid, is introduced into a hydrochemomechanical coupling, yielding a more general pressure diffusion equation. The results are compared to swelling pressure measurements for natural shale samples. The implications of this swelling pressure for water pressure measurements in natural formations are also discussed.

    Original languageEnglish
    Article numberW04514
    Pages (from-to)1-16
    Number of pages16
    JournalWater Resources Research
    Volume46
    Issue number4
    DOIs
    Publication statusPublished - 29 Apr 2010

    Fingerprint Dive into the research topics of 'What is the significance of pore pressure in a saturated shale layer?'. Together they form a unique fingerprint.

  • Cite this

    Gonçalvès, J., Gueutin, P., de Marsily, G., Cosenza, P., & Violette, S. (2010). What is the significance of pore pressure in a saturated shale layer? Water Resources Research, 46(4), 1-16. [W04514]. https://doi.org/10.1029/2009WR008090