Smith, B.D., and Archer, A.W., 1995, Geologic map, Riley County: Kansas Geological Survey, Map M-36, scale 1:50,000, 42 1/2 x 45 inches
Paper copies of the complete map (with stratigraphic column and legend info) are available from the Kansas Geological Survey, 1930 Constant Ave., Lawrence, KS 66047 (or phone 785-864-3965) and at 4150 W. Monroe St., Wichita, KS 67209-2640 (phone 316-943-2343). The cost is $15.00 plus handling and sales tax.
Jewett, J.M., 1941, The geology of Riley and Geary counties, Kansas: Kansas Geological Survey, Bulletin, no. 39, 164 pages [available online]
The Kansas Data Access and Support Center (DASC) has ArcInfo coverages available for this generalized geologic data.