Reservoirs deposited in a delta plain environment as part of the Mesaverde Formation have been penetrated by the three wells of the U.S. Department of Energy's Multiwell Experiment (MWX) in the east-central Piceance Creek basin, northwestern Colorado. These reservoirs are gas-bearing, low-permeability, sandy channel and splay deposits. Tight well spacing and an abundance of quality data from the MWX project make it possible to estimate reservoir width and orientation. Estimates of lens width were made independently by two techniques: 1) a well-to-well correlation/ probability method, and 2) by analogy to height-to-width ratios of similar lenses exposed in surface outcrops. Estimates of lens trends were made using a combination of crossbedding in oriented core, crossbedding indicated by experimental high resolution dipmeter tool, and the spatial arrangements of lens thicknesses and channel subenvironments as recognized in core and logs. Splay deposits, recognized as a different suite of lithologies and sedimentary structures in core, have less easily defined boundaries, but limits can be placed on their general position.