Gazetteer of coal-mine lakes in southwestern Indiana

Abstract

This gazetteer is a catalog of lakes formed by surface coal mining in southwestern Indiana that are 0.5 acre or larger and in nonactive mine areas. Approximately 1,000 of the lakes are listed by 7.5-minute quadrangle topographic-map name, lake-identification number, latitude and longitude, and county. Other data given are shape of lake, maximum length, mean width, length and development of shoreline, surface area, orientation, presence of a stream inlet or outlet, and geologic data (geologic formation of area surrounding the lake and the mined coal-bed member). Field data (sampling date, pH, specific conductance, apparent color of lake, and general vegetation along the shoreline) were collected for 287 of the lakes. Two-hundred eighty-seven lakes were sampled once for pH and specific conductance. Vegetation along the shoreline and apparent color of each lake were identified at the same time. Although these data are not sufficient to quantify the water quality of the lakes, they do illustrate the variability of these characteristics. The pH of the 287 lakes ranged from 2.5 to 10.0; however, the pH of 80 percent of them ranged from 6 to 9. Specific conductance ranged from 99 to 3,800 micromhos per centimeter at 25° Celsius. Specific conductance for approximately 70 percent of the lakes in the Staunton and Brazil Formations was less than 500 micromhos per centimeter at 25° Celsius, but for approximately 65 percent in the Dugger and Petersburg Formations it was greater than 1,000 micromhos per centimeter at 25° Celsius. The apparent colors of the lakes observed were varying shades of aqua, blue, brown, lime green, red, and green. Eighty percent of the lakes sampled were green. Lake sizes ranged from a chosen minimum of 0.5 acre to a maximum of 344 acres. Maximum length ranged from 0.1 to 2 miles, and the mean width was generally less than 0.8 mile. Because of the large number of lakes to be cataloged, a computer program was developed (Duke K. Bristow and Steven W. Morris, written commun., December 1977) for a Wang 2220T 1 minicomputer and digitizer to calculate latitude, longitude, and morphological data (maximum length, mean width, length and development of shoreline, surface area, and orientation) of each lake from U.S. Geological Survey 7.5-minute quadrangle topographic maps. Some of the lakes described in this report (table 2) are not on topographic maps because they were formed after the maps were prepared. An approximate location of each lake not previously shown was marked on the maps in the field. Where both field and morphological data are listed for a lake in table 2, the data are accurate to the sampling date. Where only morphological data are listed, the data were not field checked and are accurate only to the date that the topographic map was prepared. Field and geologic data were stored by the computer and were printed out with the lakelocation and morphological data. Geologic data (geologic formation of area surrounding the lake and the mined coalbed member) of the area surrounding the lakes were taken...