An expanded evaluation of thermal infrared imagery for use in the mapping of soil mantle thickness and depth to groundwater was undertaken as recommended in Part I of this report. Data were obtained over three test sites and subjected to a visual analysis. Meteorological conditions, particularly rainfall, caused the more subtle contrasts to degrade and land use practices became the most dominant signature producers on the imagery. Color enhancement did show thermal patterns that were not apparent on black and white versions of the imagery, but information related to the items of interest was not obtained. Targets having differences in temperatures located in areas characterized by uniform surface conditions provide the most optimum conditions for investigations conducted with thermal type sensors. Ground conditions must be dry over a prolonged period of time prior to data acquisition and wind conditions must be calm during the time of data acquisition. Lack of foliage is highly desirable, thus, winter or early spring data would be most advantageous. Imagery acquired during the pre-dawn or nighttime provided the best data for this project as subtle and significant thermal contrasts are not masked by differential solar heating. Significant, useful information was extracted from the imagery acquired over the Oskaloosa Area during Part I of this investigation; however, optimum ground conditions prevailed and only one geologic condition was evaluated. Because of the narrow range of climatic and geologic criteria that must be met to acquire usable and significant engineering soil data from thermal infrared imagery, it is not recommended that thermal infrared imagery be used by the State Highway Commission of Kansas on a routine basis. /FHWA/

Media Info

  • Pagination: 32 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00130692
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-75-127 Final Rpt., FCP 44E1-094
  • Contract Numbers: 70-1
  • Created Date: Mar 29 1976 12:00AM