ervoir, integration of geophysical and engineering data with geological well information is required to give the best interpretation possible. Geophysical techniques can provide information about a large fraction of the reservoir. Conventional 3D seismic data can provide structural data for an entire reservoir, but conventional surface seismic data can only image bodies of rock approximately 100 by 100 by 100 feet. Seismic data cannot, therefore, directly provide data on many of the most important reservoir properties like porosity, permeability, and fluid saturations. And while other geophysical techniques like crosswell tomography can give much finer resolution, they also do not directly provide information on porosity, permeability, and fluid saturations. Fluid flow and pressure data from wells can provide much data on bulk properties of fluid flow within a reservoir. In general, the most accurate and comprehensive estimate of reservoir characteristics results from the integration of geologic, engineering, and geophysical data.