Abandoned    Mine Lands   Land    Reclamation   Mine Safety & Training/      Blasting & Explosives   Oil & Gas

Interpreting a Mine Summary Sheet

Type: Underground denotes a subsurface mine in which the coal was reached through a shaft, slope, or drift entry. Surface denotes a surface or strip mine.

Total mined-out acreage shown: Total acreage of the mined area mapped, including any acreage mined on adjacent quadrangles. The acreage is calculated from the digitized outline of the mine. The acreage of large barrier pillars depicted on the map is excluded from the mined-out acreage. Small pillars not digitized are included in the acreage calculation. If the mine outline is not based on a final mine map, the acreage is followed by an estimate of additional acres that may have been mined. The estimate is determined from reported mine production, approximate thickness of the coal, and recovery rates calculated from nearby mines that used similar mining methods.

Shaft, slope, drift, or tipple locations: Locations of all known former entry points (Shafts, slopes, or drifts) to underground mines or the location of coal cleaning and shipping equipment used by surface mines (the tipple). The location is described in terms of township (Twp), section, and approximate footage from the section lines (EL = east line, NL = north line). Entry points are also plotted on the map and designated on the summary sheet as main shaft or air shaft on the basis of notations on the source map or other data. A mine opening may have had many purposes during the life of the mine. The tipple for underground mines was generally located near the main shaft or slope. At surface mines, coal was sometimes hauled to a central tipple several miles from the mine pit.

Seam(s) mined: The name of the coal seam(s) mined is listed if known. If multiple seams were mined, they are all listed, although the mined-out area for each seam may be shown on separate maps.

Depth: The depth to the top of the seam in the vicinity of the shaft is listed if known. The depth is determined from notes made by geologists who visited the mine during its operation or from drill hole data is ISGS files. Depth generally varies little over the extent of the mine.

Thickness: If known, the approximate thickness of the mined seam. Thickness is also determined from notes of geologists who visited the mine during its operation or from borehole data in ISGS files. Minimum, maximum, and average thicknesses are given when this information is available.

Mining method: The principal mining method used at the mine

Geologic problems reported: Any geologic problems, such as faults, water seepage, floor heaving, and unstable roof, encountered in the mine This information is from notes made by ISGS geologists who visited the mine or from reports by mine inspectors published by the Illinois Office of Mines and Minerals. Geologic problems are not reported for active mines.

Production history: Tons of coal produced from the mine by each mine owner. When the source map used for the mine outline is not a final mine map, the tonnage produced since the date of the map is identified. For mines that extend into adjacent quadrangles, the tonnage reported includes areas mined in adjacent quadrangles.

Source map: Information about the map(s) used to compile the mine outline and the locations of tipples and mine openings. In some cases more than one source map was used. For example, a map drawn before the mine closed may provide better information on original areas of the mine than a later map. When more than one map was used, the comment section explains what information was taken from each source.

Date: Date of the most recent mine survey listed on the source map.

Original Scale: Original scale of the source map. Many maps are photo-reductions and are no longer at their original scale. The original scale gives some indication of the level of detail of the mine outline and the accuracy of the mine boundary relative to surface features. Generally, the larger the scale, the greater the accuracy and detail of the mine map. Mine outlines taken from source maps at scales smaller than 1:24,000 may be highly generalized and are probably not accurately located with respect to surface features.

Digitized scale: Scale of the digitized map. The scale may be different from that of the original source map. In many cases the digitized map was made from a photo-reduction of the original source map, or the source map was not in a condition suitable for digitizing and the mine boundaries were transferred to another base map.

Map type: Source maps are classified into five categories to indicate the probable completeness of the map. See discussion of source maps in the previous section.

Annotated bibliography: Sources that provide information about the mine. Some commonly used sources are described in the Illinois Mining Bibliography.

• Return to Mining in the Springfield Quadrangle