| Results of Electrical Resistivity Data Collected near the Town of Guernsey, Platte County, Wyoming |
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| By Robert R. McDougal, Jared D. Abraham, and Robert J. Bisdorf |
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| **Open-File Report 2004–1095** |
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| **Version 1.0** |
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| Published 2004  |

| As part of a study to investigate subsurface geologic conditions as they      relate to ground-water flow in an abandoned landfill near the town of Guernsey,      Wyoming, geophysical direct current (DC) resistivity data were collected.      Eight vertical resistivity soundings and eight horizontal resistivity profiles      were made using single channel and multi-channel DC instruments. Data collected      in the field were converted from apparent resistivity to inverted resistivity      with depth using a numerical inversion of the data. Results of the inverted      resistivity data are presented as horizontal profiles and as profiles derived      from the combined horizontal profile and vertical sounding data. The data      sets collected using the single-channel and multi-channel DC systems provided      for the resistivity investigation to extend to greater depth. Similarity      of the electrical properties of the bedrock formations made interpretation      of the resistivity profiles more difficult. High resistivity anomalies      seen in the profiles are interpreted as quartzite lenses and as limestone      or metadolomite structures in the eastern part of the study area. Terrace      gravels were mapped as resistive where dry and less resistive in the saturated      zone. The DC resistivity methods used in this study illustrate that multi-electrode      DC resistivity surveying and more traditional methodologies can be merged      and used to efficiently map anomalies of hydrologic interest in geologically    complex terrain. |
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| - OF 2004–1095 PDF            file (61.5 MB)   **** Large File Warning!! **** | **For viewing and printing.** |
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| Text-Only PDF                      file (88 KB) | **Text-only version of the report.***(This version of the report is  accessible as      defined in Section 508.)* |
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| -  Database files | **North-south trending resistivity profiles from combined        SuperSting and vertical sounding data.** Profiles are aligned to common UTM northing coordinates.    Profile locations are shown in figure 2. |
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| All files used to produce the resistivity profiles        in this report are included and listed by    directory as follows: |
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| - sting_profiles                                                                                                             | **Eight lines of resistivity data collected with the        AGI SuperSting system.**      Each line directory includes: original        .dat inverted resistivity data, Surfer v.8 plot files, .grd grid files,        and .bln blanking files, and Excel    spreadsheet of data and coordinates. |
| - sounding_profiles                                                                                                          | **Eight lines of combined resistivity data collected        the AGI SuperSting system and ABEM single-channel system.** Each line directory includes:      original      .dat inverted resistivity data, Surfer v.8 plot files, .grd grid files,    and .bln blanking files, and Excel spreadsheet of data and coordinates. |

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| U.S. Department of the Interior | U.S. Geological Survey      URL: https://pubsdata.usgs.gov/pubs/of/2004/1095/Questions or Assistance: USGS Web ContactPage Last Modified: Sat Jan 12 23:15 EDT 2013 |  |

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