Circular 589: Appendix

The remote sensing data resources, including the aerial photographs, vegetated crop line features, LiDAR shaded relief images, sinkholes and mine digging alignments produced and used for this investigation are included as four online collections with this publication. Locations of the collections are shown on figures A1–A4, tables A1– A4, and on the main map.

Crop Line Aerial Photos August 2012 - contains the natural color, vertical aerial photographs acquired by the Illinois Department of Transportation on August 28, 2012, as a reconnaissance mission for this study to record vegetated crop lines for 15 selected project areas within Jo Daviess County, Illinois. Figure A1 shows the location of each of the 15 flight lines or strips (ST) of aerial photographs on a regional map of the study area, and table A1 is a listing of the groups of aerial photographs by strip ID and Township-Range.

The film-based aerial photography was acquired using a 9”x 9” format Wild aerial camera, and the original film was digitized for each 9” x 9” frame using a high-precision Leica aerial film scanning system at 2,032 dpi to produce fullresolution, archive TIFF images (approx. 1 GB/image). The online collection contains 58 individual frames selected from the original 104 aerial photographs, each of which illustrates vegetated crop lines. In order to reduce the file size for the online collection, high-quality 300 dpi JPEG images were produced from the each archival TIFF. The full-resolution TIFF images are available upon request.

Although acquired in a vertical orientation, the digitized aerial photographs have not been georeferenced or orthorectified using ground control; therefore vegetated crop lines visible in each of the aerial photographs were not digitized. Although the images are not georeferenced, each is oriented north-up to facilitate interpretation.

Crop Line Aerial Photos September 2012 - contains the vertical aerial photographs (September 27, 2012 acquisition date) captured from Google Earth® using the Shape2Earth® image capture program, which preserves the georeferencing information for the purpose of facilitating GIS and mapping analyses. Figure A2 shows their location on a regional map of the study area, and table A2 is a listing of the aerial photographs by ID and Township-Range.

The vegetated crop lines exhibited on each of the 128 aerial photographs were digitized using ArcGIS®, and the resulting database of 17,855 vegetated crop lines served as the basis for the fracture/crevice analyses.

The Shape2Earth® captured vertical aerial photographs and vegetated crop line features were exported directly from the original GIS project database to create layered PDFs. Selecting the Layers navigation panel in Adobe Acrobat Reader or Acrobat Professional (View>Navigation Panels>Layers), the user can toggle on/off the data layers features in order to separately view the vegetated crop line features and the original aerial photograph. The original ArcGIS® file geodatabase containing the georeferenced aerial photographs and digitized crop line features is available upon request.

Sinkholes - contains shaded relief images produced from 2008 bare earth LiDAR for 42 areas within Jo Daviess County that illustrate alignments of sinkhole features. The alignments interpreted directly from the LiDAR data were digitized using ArcGIS®. Figure A3 shows their location on a regional map of the study area, and table A3 is a listing of the sinkhole areas by ID and Township-Range. The LiDAR shaded relief images and digitized sinkhole alignments were exported directly from the original GIS project database to create layered PDFs. Selecting the Layers navigation panel in Adobe Acrobat Reader or Acrobat Professional (View>Navigation Panels>Layers), the user can toggle on/ off the data layers features in order to separately view the sinkhole alignments and the LiDAR shaded relief image. The original ArcGIS® file geodatabase containing the LiDAR images and sinkhole alignments is available upon request.

Mine Diggings - contains shaded relief images produced from 2008 bare earth LiDAR for 84 areas within Jo Daviess County that illustrate alignments of lead-zinc mine diggings. The alignments interpreted directly from the LiDAR data were digitized using ArcGIS®. Figure A4 shows the mine digging locations on a regional map of the study area, and table A4 is a listing of the mine digging areas by ID and Township-Range. The LiDAR shaded relief images and digitized mine diggings alignments were exported directly from the original GIS project database to create layered PDFs. Selecting the Layers navigation panel in Adobe Acrobat Reader or Acrobat Professional (View>Navigation Panels>Layers), the user can toggle on/off the data layers features in order to separately view the mine digging alignments and the LiDAR shaded relief image. The original ArcGIS® file geodatabase containing the LiDAR images and mine digging alignments is available upon request.