Plate No. I. Sample location overlay for the Craig NTMS quadrangle, Colorado. pocket II. Uranium concentrations (ppb) in watersoverlay to the Craig NTMS quadrangle, Colorado. pocket III. Conductivities (yimho/cm) in watersoverlay to the Craig NTMS quadrangle, Colorado. pocket IV. Uranium concentrations (ppm) in sedimentsoverlay to the Craig NTMS quadrangle, Colorado. pocket V. Thorium concentrations (ppm) in sedimentsoverlay to the Craig NTMS quadrangle, Colorado. pocket LIST OF TABLES Table No. I. Principal Rock Units in the Craig Quadrangle, Colorado 6 II. Generalized Descriptions of Major Uranium Districts in the Craig Quadrangle, Colorado 10 III. Summary of Uranium Data for Water Samples from the Craig Quadrangle, Colorado 13 IV. Clusters of Water Samples with Anomalous Uranium Concentrations (greater than 10 ppb) from the Craig Quadrangle, Colorado 15 V. Summary of Uranium Data for Sediment Samples from the Craig Quadrangle, Colorado 17 VI. Clusters of Sediment Samples with Anomalous Uranium Concentrations (greater than 20 ppm) from the Craig Quadrangle,