A closer look at rock physics models and their assisted interpretation in seismic exploration

Subsurface rocks and their fluid content along with their architecture affect reflected seismic waves through variations in their travel time, reflection amplitude, and phase within the field of exploration seismology. The combined effects of these factors make subsurface interpretation by using reflection waves very difficult. Therefore, assistance from other subsurface disciplines is needed if we intend to make a more accurate image of the subsurface. In this regard, rock physics acts as an integrated tool to combine subsurface information from different disciplines in a set of relationships between engineering (petrophysical) properties and their relevant geophysical variations, or more specifically, elastic variations. As a matter of fact, rock physics is required for a better understanding of rock properties if we intend to have a full understanding of our reservoir properties and their fluid content. This paper reviews some of the most important rock physics models and their application within the field of seismic exploration. These models are generally valid for the given conditions in which they are derived, and as a result, having a good understanding of their physical and geological limitations can help a lot with accurate rock physics modeling and interpretation. In this regard, this paper is an attempt to create a better understanding of such models, using different references and my personal experiences with these models. The application contexts of the models presented in this paper are not limited to the discussed scenarios. These scenarios are the ones that are commonly used and have shown a good prediction power in practice.