Physical Sciences and Mathematics Commons^™

Effects Of Stress And Water Saturation On Seismic Velocity And Attenuation In Near Surface Sediments, James Michael Crane

LSU Doctoral Dissertations

Seismic investigation in the near-surface is complicated by highly attenuating media, large interparticle stresses, and variable water saturation, so new tools and methodology are necessary to understand the relationships between velocity, attenuation, and physical properties of the propagating media. A new shear wave source is developed for investigation of gas-charged, organic-rich sediments because compressional waves are highly attenuated and currently available sources are inadequate. The new source compares favorably to a traditional hammer impact source, producing a signal with a broader-band of frequencies (30-100Hz cf. 30-60Hz) and signal-to-noise ratios (SNR) equivalent to ~3 stacked hammer blows to the hammer impact …