Comparison of CO2 trapping in highly heterogeneous reservoirs with Brooks-Corey and van Genuchten type capillary pressure curves

Naum I. Gershenzon, Robert W. Ritzi, David F. Dominic, Edward Mehnert, Roland T. Okwen

Research output: Contribution to journalArticle

Abstract

Geological heterogeneities affect the dynamics of carbon dioxide (CO2) plumes in subsurface environments in important ways. Previously, we showed how the dynamics of CO2 plumes are influenced by the multiscaled sedimentary architecture in deep brine fluvial-type reservoirs. The results confirm that representing small-scale features and the corresponding heterogeneity in saturation functions, along with hysteresis in saturation functions, are all critical to understanding capillary trapping processes. Here, we show that when heterogeneity and hysteresis are represented, the two conventional approaches for defining saturation functions, Brooks-Corey and van Genuchten, represent fundamentally different physical systems. The Brooks-Corey approach represents heterogeneity in entry pressures, and leads to trapping by capillary pinning. The van Genuchten approach represents a network of pores transporting the nonwetting fluid, across rock types, with negligible capillary entry pressure, and leads to capillary retardation. These differences significantly affect the large-scale characteristics of CO2 plumes (i.e., their mass, shape, and position).

Original languageEnglish (US)
Pages (from-to)225-236
Number of pages12
JournalAdvances in Water Resources
Volume96
DOIs
StatePublished - Oct 1 2016

Keywords

  • Brooks-Corey
  • CO geosequestration
  • Capillary trapping
  • Heterogeneity
  • Sedimentary architecture
  • van Genuchten

ASJC Scopus subject areas

  • Water Science and Technology

Fingerprint Dive into the research topics of 'Comparison of CO<sub>2</sub> trapping in highly heterogeneous reservoirs with Brooks-Corey and van Genuchten type capillary pressure curves'. Together they form a unique fingerprint.

  • Cite this