HR: 16:40h
AN: NS34A-05    [Abstracts]
TI: Investigation of the Near Subsurface Using Acoustic to Seismic Coupling
AU: * Howard, W B
EM: wbhoward@olemiss.edu
AF: National Center for Physical Acoustics University of Mississippi, 1 Coliseum Drive, Universtiy, MS 38677 United States
AU: Hickey, C J
EM: chickey@olemiss.edu
AF: National Center for Physical Acoustics University of Mississippi, 1 Coliseum Drive, Universtiy, MS 38677 United States
AU: Sabatier, J M
EM: sabatier@olemiss.edu
AF: National Center for Physical Acoustics University of Mississippi, 1 Coliseum Drive, Universtiy, MS 38677 United States
AB: Agricultural, hydrological, and civil engineering applications have lead to a need for high resolution information of the near subsurface over large areas. In order to obtain this high resolution data over a large area, the measurement technique must be highly mobile with a short acquisition time. For this reason, ground penetrating radar (GPR) has seen much use for these applications. We propose to use acoustic to seismic (A/S) coupling to investigate the mechanical properties and stratification of the near subsurface down to a depth of a few meters. In this technique, seismic waves are created via the coupling of airborne energy into the ground surface. An airborne source has the benefit of being non-contact (mobile) and allowing for high frequency (high resolution) investigation of the subsurface. Sensors, either geophones or laser doppler vibrometers, record the resulting solid particle motion at the surface due to energy reflected from interfaces between dissimilar media at depth. Interference between waves produce a frequency response curve containing information about the distribution of mechanical properties of the near-surface soil. We will discuss the results of the A/S coupling measurements in relation to shallow seismic and cone penetrometer measurements obtained at an agricultural field site and how these measurements relate to a spatially variable genetic hard pan
DE: 1875 Unsaturated zone
DE: 1894 Instruments and techniques
DE: 5102 Acoustic properties
SC: Near-Surface Geophysics [NS]
MN: 2005 Joint Assembly