A 17.2-by-17.0-cm-diam right-circular cylinder of oil shale was retorted between 25 and 900supO/C at a heating rate of 18supO/C/h. A computational model was developed to simulate the block heat-up and reaction chemistry. This one-dimensional model, which contains the heat-transport equation and 10 chemical reactions based on laboratory kinetics of powdered samples, provides a good estimation of the experimental results. The model predicted the temperature profile through the block to within approximately 15supO/C of the measured value. The predicted total mass loss, oil yield, and details of the evolution of individual products were generally in close agreement with the experiment. Only the extent of CO evolution differed significantly from the experiment.