Impact of pore fluid chemistry on fine‐grained sediment fabric and compressibility
Cao, Shuang C.
Stern, Laura A.
Waite, William F.
MetadataShow full item record
KeywordFine‐grained sediment fabric; Electrical sensitivity; Pore‐fluid chemistry; Sedimentation; Compressibility; Methane hydrate
Fines, defined here as grains or particles, less than 75 μm in diameter, exist nearly ubiquitously in natural sediment, even those classified as coarse. Macroscopic sediment properties, such as compressibility, which relates applied effective stress to the resulting sediment deformation, depend on the fabric of fines. Unlike coarse grains, fines have sizes and masses small enough to be more strongly influenced by electrical interparticle forces than by gravity. These electrical forces acting through pore fluids are influenced by pore fluid chemistry changes. Macroscopic property dependence on pore fluid chemistry must be accounted for in sediment studies involving subsurface flow and sediment stability analyses, as well as in engineered flow situations such as groundwater pollutant remediation, hydrocarbon migration, or other energy resource extraction applications. This study demonstrates how the liquid limit‐based electrical sensitivity index can be used to predict sediment compressibility changes due to pore fluid chemistry changes. Laboratory tests of electrical sensitivity, sedimentation, and compressibility illustrate mechanisms linking microscale and macroscale processes for selected pure, end‐member fines. A specific application considered here is methane extraction via depressurization of gas hydrate‐bearing sediment, which causes a dramatic pore water salinity drop concurrent with sediment being compressed by the imposed effective stress increase.
Author Posting. © American Geophysical Union, 2018. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 123 (2018): 5495-5514, doi:10.1029/2018JB015872.
The publisher requires that this item be embargoed until 2019-01-17. Please check back after 2019-01-17.
Suggested CitationArticle: Jang, Junbong, Cao, Shuang C., Stern, Laura A., Kang, Jungwon, Waite, William F., "Impact of pore fluid chemistry on fine‐grained sediment fabric and compressibility", Journal of Geophysical Research: Solid Earth 123 (2018): 5495-5514, DOI:10.1029/2018JB015872, https://hdl.handle.net/1912/10586
Showing items related by title, author, creator and subject.
Flow and sediment properties influencing erosion of fine-grained marine sediments : sea floor and laboratory experiments Young, Robert Alexander (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1975-09)Erosion processes involving fine-grained marine sediments were studied by using an in situ flume to erode undisturbed bottom sediments on the sea floor in Buzzards Bay, a shallow marine embayment off the Massachusetts coast. ...
Focusing of upward fluid migration beneath volcanic arcs : effect of mineral grain size variation in the mantle wedge Wada, Ikuko; Behn, Mark D. (John Wiley & Sons, 2015-11-13)We use numerical models to investigate the effects of mineral grain size variation on fluid migration in the mantle wedge at subduction zones and on the location of the volcanic arc. Previous coupled thermal-grain size ...
Rubin, David M.; Chezar, Henry; Harney, Jodi N.; Topping, David J.; Melis, Theodore S.; Sherwood, Christopher R. (Elsevier B.V., 2007-05-26)For more than a century, studies of sedimentology and sediment transport have measured bed-sediment grain size by collecting samples and transporting them back to the laboratory for grain-size analysis. This process is ...