Occurrence and Distribution of Minerals in Illinois Coals

摘要: Analysis of mineral matter from coals the Illinois Basin revealed six common minerals, identified trace and allowed development a model depositional environment for Herrin (No. 6) coal. Sixty-five coal samples, majority (41) coal, were low-temperature-ashed, followed by quantitative x-ray diffraction analysis determination, computation mean concentration standard deviation each mineral. Most clays (illite, kaolinite, mixed-layer clays), pyrite, quartz, calcite. Trace minerals included siderite, dolomite, feldspar, gypsum, marcasite, sphalerite. Iron sulfate resulting pyrite oxidation in all but extremely fresh samples. The distribution may best be interpreted as response to both general northeast southwest paleoslope, presence distributary channel system contemporaneous with swamp. Calcite, illite, expandable clay respond paleoslope illite preferentially deposited landward, calcite basinward. Concentrations are influenced high kaolinite low bordering channel.