"Electrical resistivity tomography and multi-channel analyses of surface waves data were acquired at a study area in Phelps County in the south-central part of Missouri. The objectives of the investigation were fourfold: 1) to image the subsurface in the study area to a depth of 70 feet; 2) to compare the ERT images generated using both the dipole-dipole and Wenner-Schlumberger arrays; and 3) to assess how variations in the MASW array configuration affected MASW data quality; and 4) to compare the ERT-estimated depth to top-of-rock and the MASW-generated depth to top-of-rock.
The subsurface in the study area was imaged to a depth of 70 feet using the ERT tool. Soils were categorized as either dry, moist or moist and clayey. Limestone bedrock was also imaged and categorized as weathered or intact. The top-of-rock, as per the ERT interpretations, was consistent with the MASW-estimated depths to top-of-rock and correlated well with the 70 ohm-m contour value.
Based on the comparative analyses of the dipole-dipole array ERT data, the Wenner-Schlumberger array ERT data and MASW 1-D shear-wave data, it is concluded that the Wenner-Schlumberger array ERT data are slightly more consistent with the MASW data in terms of estimated depth to top-of-rock and dip direction of subsurface layers. However, the dipole-dipole array ERT data appear to better image limestone bedrock (in terms of lateral resolution). Based on the analyses of the MASW data, it is concluded that better results were obtained using a 2.5-foot geophone spacing (as opposed to a 5-foot spacing), probably because depth to top-of-rock varies significantly in places in the study area"--Abstract, page iii.
Anderson, Neil L. (Neil Lennart), 1954-
Torgashov, Evgeniy V.
Liu, Kelly H.
Geosciences and Geological and Petroleum Engineering
M.S. in Geological Engineering
Missouri University of Science and Technology
xii, 77 pages
© 2017 Ragab W Jaafar, All rights reserved.
Thesis - Open Access
Electronic OCLC #
Jaafar, Ragab W., "Imaging in karst terrain using the electrical resistivity and multichannel analyses of surface wave methods" (2017). Masters Theses. 7687.