We use rock physics models for poorly consolidated rocks to diagnose reservoir sandstones in the Alvheim Field, North Sea. Geological factors that will control the rock physics and seismic properties include clay content, sorting, diagenesis, mineralogy, and bedding configuration. The various geologic factors will affect the fluid and stress sensitivity in these rocks. We investigate the interrelationships between various geological factors and seismic fluid and stress sensitivity, by combining well log data and rock physics models. Finally, we determine inter-well characteristics in terms of varying geological factors at different locations and discuss the results in terms of expected seismic signatures in the area.