Of the numerous sedimentational factors used to relate the paleochannel sandstones of the Duchesne River Formation to their source in the Uinta Mountains, one of the more interesting is the type and quantity of cement which binds the sands. Three stages of cementation are revealed by thin section analysis--major primary and secondary stages, and a minor tertiary stage. Distribution patterns of the primary cement seem to be closely related to source rock and distance of transport. Those of the secondary cement are more closely related to structure and source rock and imply a groundwater influence. If these relationships should prove common to other similar deposits it might be possible to establish cement as an index to such things as structure, drainage directions of both surface and subsurface water, permeability, distance of transport, and source rock. To accomplish this task the following efforts should be made: 1. Experimentation with chemical conditions within the ranges of natural environments. 2. Greater detailed mapping of cement distribution and other structural and sedimentational factors in known ground water and petroleum reservoirs. 3. More, and better, petrographic studies of relationships between cement and the fabric and texture of rocks of known reservoirs.