2026-09-23T01:52:58Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/87722 2023-07-11 col_2142_5131 col_2142_46414 com_2142_5130 com_2142_178 com_2142_234

160 p. Harris, John G. Block, Gareth Ian 2015-09-28T16:23:40Z 2015-09-28T16:23:40Z 10000-01-01 2004 2004 "We devised two reciprocal experiments to study these phenomena. ""EK transmission"" occurs when an applied voltage creates an electro-acoustic wave; in practice, this leads to thermoelastic motion, as well as electrokinetics, so that we have had to account for both effects. Conversely, ""EK reception"" occurs when a pressure wave generates a measurable voltage in electrolyte-saturated sediments. The EK reception apparatus made use of a submerged, acoustic transducer to insonify a water-sediment interface with short, 50 kHz sine-wave bursts and chirped pulses from 10--800 kHz. The resulting wave motion was monitored using Ag/AgCl electrodes fixed in a vertical array above and below the sediment interface. We measured the conductivity dependence of two kinds of EK behavior: (1) voltages generated within the samples that were localized around the transmitted ""fast"" waves, and (2) electromagnetic (EM) waves produced at the water-sediment interface. Fast-wave voltages were often greater than 500 muV, while the EM-wave potentials were usually 100 muV in magnitude. A model of plane-wave reflection from a water-EK-Biot interface leads to theoretical predictions that compare very well to experimental data for sand and glass microspheres. Both EM- and fast-wave voltages are caused by relative fluid motion in the sediment, a feature that is characteristic of poroelastic media---but not predicted by either fluid or solid models." Made available in DSpace on 2015-09-28T16:23:40Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3153250.pdf: 15857075 bytes, checksum: dfe7eca1a1a799f22cddbd4626df1d7a (MD5) Previous issue date: 2004 Embargo set by: Seth Robbins for item 89003 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004. http://hdl.handle.net/2142/87722 (MiAaPQ)AAI3153250 eng Physical Oceanography Coupled Acoustic and Electromagnetic Disturbances in a Granular Material Saturated by a Fluid Electrolyte text Theoretical and Applied Mechanics Theoretical and Applied Mechanics University of Illinois at Urbana-Champaign Dissertation Ph.D.