Investigation of a Damsite Utilizing Drill-hole, Down-hole Geophysical and Surface Geophysical Data

Abstract

Research Article| January 01, 1978 Investigation of a Damsite Utilizing Drill-hole, Down-hole Geophysical and Surface Geophysical Data ROBERT B. JOHNSON; ROBERT B. JOHNSON Robert B. Johnson is with the Dept. of Earth Resources, Colorado State University, Fort Collins, Colorado. Search for other works by this author on: GSW Google Scholar LYNN A. JOHNSON LYNN A. JOHNSON Lynn A. Johnson is with the U.S. Bureau of Reclamation, Denver, Colorado. Search for other works by this author on: GSW Google Scholar Environmental & Engineering Geoscience (1978) xv (3): 285–294. https://doi.org/10.2113/gseegeosci.xv.3.285 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation ROBERT B. JOHNSON, LYNN A. JOHNSON; Investigation of a Damsite Utilizing Drill-hole, Down-hole Geophysical and Surface Geophysical Data. Environmental & Engineering Geoscience 1978;; xv (3): 285–294. doi: https://doi.org/10.2113/gseegeosci.xv.3.285 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract The proposed site of an earth dam for the Bureau of Reclamation's Nebraska Mid-State Project presents a complex foundation problem involving alluvial fill in a buried channel cut in similar sediments of Tertiary age. Three drill holes provided control of stratigraphy, material types and unit thicknesses. Electric and gamma-ray logs were run to obtain geophysical data for the materials encountered. Surface geophysics was employed to determine the lateral extent, changes in materials and thickness, and channel configuration of the units noted in the drill-hole and geophysical log data.The physical properties of the materials restricted the use of surface geophysics. Electrical earth resistivity provided the only means of separating and mapping the units on the basis of electrical contrasts provided by the electric logs. Gamma-ray log data served to reinforce electric log and drill-hole correlations.Empirical interpretation of total resistivity and Lee partitioning curves were employed for correlation of resistivity and drill-hole data and for interpretation of lateral changes and extrapolation of subsurface conditions between drill holes. Curve fitting techniques provided a means of obtaining a geophysical overview of the survey uncomplicated by minor unit differences.The integrated use of drill-hole, geophysical well log and surface geophysical data permitted development of a materials profile along the section of dam involved. Further drilling may now be done at those sites shown to present critical interfacing of potentially troublesome materials. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.