Evaporation from Fractures Exposed at the Land Surface: Impact of Gas-Phase Convection on Salt Accumulation

Noam Weisbrod, Modi Pillersdorf, Maria Dragila, Chris Graham, James Cassidy, Clay A. Cooper

Research output: Chapter in Book/Report/Conference proceedingChapterpeer-review

4 Scopus citations

Abstract

A mechanism is investigated by which surface-exposed fractures could be a source of aquifer salinization in low-permeability fractured formations under arid conditions. It is hypothesized that evaporation of pore water within surfaceexposed fractures is enhanced by convective air circulation within those fractures that vents moisture to the atmosphere. This evaporation also simultaneously enhances lateral movement of pore water from the adjacent matrix towards the fracture surface, permitting dissolved solutes to precipitate on the surface and form a crust. The salt crust can then dissolve during infiltration events and be flushed downward to the aquifer. Theoretical analysis shows that convective venting is expected during cool nights when atmospheric air is denser than the fracture air. Laboratory experiments support the hypothesis of rapid salt-crust formation in the presence of convectively moving air across a fracture face. A numerical model is developed and used to quantify the buildup of salt on a fracture face.

Original languageEnglish
Title of host publicationDynamic Fluids and Transport Through in Fractured Rock
PublisherAmerican Geophysical Union
Pages151-164
Number of pages14
ISBN (Electronic)9781118666173
ISBN (Print)0875904270, 9780875904276
DOIs
StatePublished - 29 Mar 2013

Keywords

  • Groundwater flow-Mathematical models
  • Rocks-Permeability-Mathematical models

ASJC Scopus subject areas

  • General Physics and Astronomy

Fingerprint

Dive into the research topics of 'Evaporation from Fractures Exposed at the Land Surface: Impact of Gas-Phase Convection on Salt Accumulation'. Together they form a unique fingerprint.

Cite this