A survey of the literature indicates that, compared to shales and sandstones, relatively little micropetrographic work (SEM-EDX, electron probe) has been done on authigenic and diagenetic clay minerals in carbonate rocks. This project is a micropetrographic investigation of the Upper Mississippian shelf-tidal flat carbonates, which occur in excellent exposures along the edge of the Cumberland Plateau (TN). These rocks contain a wide variety of possible authigenic/diagenetic clay minerals (Ch/S, Ch/V, corrensite, vermiculite, illite, I/S). A preliminary SEM-EDX study (Fig. 1-3) confirms the presence of authigenic/diagenetic I/S (4:1) in the interior of calcite oolites. The study will concentrate on the Upper Mississippian carbonates and establish the genetic relation of the Mg clays and K clays to calcite, dolomite and the various shallow carbonate environments. In addition to chemical, mineralogical, and petro- graphic data will be obtained on spatial and volume data so that mass balance calculations can be made for Mg and other ions. In addition to obtaining information of the origin of the clay minerals, we will obtain information on the factors effecting the partitioning of Mg between silicate and carbonate minerals. The goal of this research is to determine the nature, significance of clay mineral reactions in carbonate rocks, shedding light on diagenetic processes.
