The Illinois State Geological Survey is conducting geological and geochemical investigations to evaluate the potential of New Albany Group shales as sources of hydrocarbons. Geological studies include stratigraphy and structure; mineralogic and petrographic characterization; analyses of physical properties; and development of a computer-based resources evaluation system. Studies include quantitative determination of 49 major, minor, and trace elements; trace element distribution between inorganic and organic phases; hydrocaron characterization; and adsorption/desorption studies of gas through shales. Six cores (five from Illinois and one from western Kentucky) provide the principal data base for these investigations. Using subsurface stratigraphic techniques, twenty-two cross-sections and a preliminary New Albany Group thickness map have been prepared. Isopach maps are in preparation for each of the formations within the New Albany. Black shales predominate in the center of the Illinois Basin, whereas gray shales predominate around the margins of the Basin. A computer data base of over 5000 wells penetrating the New Albany Group has been compiled. Tectonic origins are not postulated for any of the linears, and caution is advised when interpreting linear features in glaciated terrains. Mineralogic and petrographic studies have concentrated on two cores. A preliminary classification of four shales lithofacies based on primary depositional characteristics has been established and related to oxygenation of the bottom environment. Preliminary results of physical index properties; major, minor, and trace elements; and gas compositions have been obtained for three cores. Internal surface area measurements reveal that gray shales have higher ultramicroporosity than do black shales. The gray shales also have high gas diffusion rates and are better reservoir rocks.